CVE-2026-16770

CRITICALPre-NVD 9.89.8
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-13. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: CISA-ADP (Vulnrichment) CVSS v3.1, EPSS, GitHub Security Advisory

Also known asEUVD-2026-57695 (ENISA EUVD) · GHSA-6f7m-6567-58mj (GitHub Security Advisories)Source: ENISA EUVD

9.8EG
EchelonGraph verdictPlan mitigationNo release containing the referenced fix is confirmed: check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.7%CVSS: 9.8Exploit: None knownExposed services: Not assessed

A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).

PDF::WebKit versions through 1.2 for Perl allow argument injection into wkhtmltopdf via meta tags in the source document.

For an HTML string or file source, the constructor collects every element in the document head through _pdf_webkit_meta_tags and turns each one into a wkhtmltopdf command line option. KEY is normalized to an option name matching --[a-z0-9-]+ but is not checked against an allow list, VALUE is passed through unchanged as the argument that follows it, and a VALUE of "yes" emits the option as a bare flag. BUILD merges the meta derived options last, so they also override the module defaults and the options passed to new. Switches such as --enable-local-file-access and --cookie-jar are reachable this way. The renderer is executed with an argument list rather than a shell command, so this is argument injection and not shell injection.

Any caller that renders untrusted HTML lets the document choose the renderer's options and override those set by the application, including options that read local files into the resulting PDF or write to a chosen path. A URL source is not scanned, and the scan is skipped when XML::LibXML, a recommended dependency, is not installed.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
59
EG Risk 59/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.7% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high.
EPSS PROB
0.7%
EPSS %ILE
54th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.7% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-12). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 3 days if the affected system is publicly exposed; 60 days if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).

A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)3 days if the affected system is publicly exposed; 60 days if it is not.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

August 12, 2026

Last Modified

October 23, 2026

Advisory Details (4)

Auto-updated Nov 7, 2026
Fix referenced — no release confirmed yet.
Web page

oss-security - CVE-2026-16770: PDF::WebKit versions through 1.2 for Perl allow argument injection into wkhtmltopdf via meta tags in the source document

http://www.openwall.com/lists/oss-security/2026/08/13/2
Web page

wkhtmltopdf argument injection via HTML <meta> tags · Issue #9 · kingpong/perl-PDF-WebKit · GitHub

https://github.com/kingpong/perl-PDF-WebKit/issues/9

Vendor Advisories for CVE-2026-16770(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 13× in last 7d / 58× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed its CVE.org record (CNA or CISA ADP). An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

Showing the most recent 100 of 483 rows on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 383 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-13 16:51 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  2. 2026-11-13 02:19 UTCEchelonGraph re-scored
  3. 2026-11-13 02:19 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  4. 2026-11-12 16:33 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  5. 2026-11-12 00:57 UTCEchelonGraph re-scored
  6. 2026-11-12 00:57 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  7. 2026-11-11 16:38 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  8. 2026-11-10 23:35 UTCEchelonGraph re-scored
  9. 2026-11-10 23:34 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  10. 2026-11-10 16:42 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  11. 2026-11-09 22:09 UTCEchelonGraph re-scored
  12. 2026-11-09 22:09 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  13. 2026-11-09 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  14. 2026-11-08 20:42 UTCEchelonGraph re-scored
  15. 2026-11-08 20:42 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  16. 2026-11-08 16:38 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  17. 2026-11-07 19:20 UTCEchelonGraph re-scored
  18. 2026-11-07 19:20 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  19. 2026-11-07 16:38 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  20. 2026-11-06 17:56 UTCEchelonGraph re-scored
  21. 2026-11-06 17:56 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  22. 2026-11-06 16:36 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  23. 2026-11-06 01:25 UTCOSV refresh
  24. 2026-11-05 16:36 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  25. 2026-11-05 16:34 UTCEchelonGraph re-scored
Show 75 more
  1. 2026-11-05 16:34 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  2. 2026-11-04 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  3. 2026-11-04 15:10 UTCEchelonGraph re-scored
  4. 2026-11-04 15:10 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  5. 2026-11-03 16:47 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  6. 2026-11-03 13:47 UTCEchelonGraph re-scored
  7. 2026-11-03 13:47 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  8. 2026-11-02 16:44 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  9. 2026-11-02 12:10 UTCEchelonGraph re-scored
  10. 2026-11-02 12:10 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  11. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  12. 2026-11-01 10:47 UTCEchelonGraph re-scored
  13. 2026-11-01 10:47 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  14. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  15. 2026-10-31 09:26 UTCEchelonGraph re-scored
  16. 2026-10-31 09:26 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  17. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  18. 2026-10-30 08:03 UTCEchelonGraph re-scored
  19. 2026-10-30 08:03 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  20. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  21. 2026-10-29 06:41 UTCEchelonGraph re-scored
  22. 2026-10-29 06:41 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  23. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  24. 2026-10-28 05:19 UTCEchelonGraph re-scored
  25. 2026-10-28 05:19 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  26. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  27. 2026-10-27 03:57 UTCEchelonGraph re-scored
  28. 2026-10-27 03:56 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  29. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  30. 2026-10-25 22:19 UTCEchelonGraph re-scored
  31. 2026-10-25 22:19 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  32. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  33. 2026-10-25 14:46 UTCEchelonGraph re-scored
  34. 2026-10-24 20:50 UTCEchelonGraph re-scored
  35. 2026-10-24 20:50 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  36. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  37. 2026-10-23 19:29 UTCEchelonGraph re-scored
  38. 2026-10-23 19:28 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  39. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  40. 2026-10-23 06:30 UTCEchelonGraph re-scored
  41. 2026-10-23 06:30 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  42. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  43. 2026-10-22 05:08 UTCEchelonGraph re-scored
  44. 2026-10-22 05:07 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  45. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  46. 2026-10-21 03:42 UTCEchelonGraph re-scored
  47. 2026-10-21 03:42 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  48. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  49. 2026-10-20 02:17 UTCEchelonGraph re-scored
  50. 2026-10-20 02:17 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  51. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  52. 2026-10-19 00:54 UTCEchelonGraph re-scored
  53. 2026-10-19 00:53 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  54. 2026-10-18 04:00 UTCEchelonGraph re-scored
  55. 2026-10-17 23:31 UTCEchelonGraph re-scored
  56. 2026-10-17 23:31 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  57. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  58. 2026-10-16 22:08 UTCEchelonGraph re-scored
  59. 2026-10-16 22:07 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  60. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  61. 2026-10-15 18:40 UTCEchelonGraph re-scored
  62. 2026-10-15 18:40 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  63. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  64. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  65. 2026-10-14 12:20 UTCEchelonGraph re-scored
  66. 2026-10-14 12:19 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  67. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  68. 2026-10-13 10:57 UTCEchelonGraph re-scored
  69. 2026-10-13 10:57 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  70. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  71. 2026-10-12 16:30 UTCEchelonGraph re-scored
  72. 2026-10-12 09:33 UTCGHSA enrichmentGHSA-6f7m-6567-58mj · GitHub severity CRITICAL · GitHub CVSS 9.8
  73. 2026-10-11 20:09 UTCEchelonGraph re-scored
  74. 2026-10-11 17:21 UTCEchelonGraph re-scored
  75. 2026-10-11 14:54 UTCEchelonGraph re-scored

Frequently asked(5)

What is CVE-2026-16770?
CVE-2026-16770 is a critical-severity vulnerability; its CVE record was published on August 12, 2026. PDF::WebKit versions through 1.2 for Perl allow argument injection into wkhtmltopdf via meta tags in the source document. For an HTML string or file source, the constructor collects every <meta name="pdf-webkit-KEY" content="VALUE"> element in the document head through _pdf_webkit_meta_tags and…
When was the CVE record for CVE-2026-16770 published?
The CVE record for CVE-2026-16770 was published on August 12, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 23, 2026; the record at its source may have been updated since.
Is CVE-2026-16770 actively exploited?
CVE-2026-16770 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.7% probability of exploitation in the next 30 days (54th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-16770?
CVE-2026-16770 has a CVSS v3.1 base score of 9.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-16770?
A fix for CVE-2026-16770 is referenced (a reference tagged "Patch", often a source commit), but EchelonGraph has no release containing it on record. Check that reference and the vendor's advisory for a release that contains the fix and update to it; until then, restrict network exposure of the affected system or apply the vendor's mitigation. The vendor advisories EchelonGraph has for CVE-2026-16770 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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