CVE-2026-18568

HIGHPre-NVD 7.57.5
EchelonGraph scoreMEDIUM confidence

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

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-08-03. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 7.5; 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-2026-52325 (ENISA EUVD) · GHSA-r3hj-rg3j-262c (GitHub Security Advisories)Source: ENISA EUVD

7.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines 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: 0.3%CVSS: 7.5Exploit: None knownExposed services: Not assessed

Upgrade to XML::Sig 0.72 or later, which returns false when no reference digest was checked and matched (from the CVE record's solution, CPAN Security Group) — apply it.

XML::Sig versions from 0.29 before 0.72 for Perl allow signature verification bypass because verify returns true when every signature was skipped before any cryptographic check.

verify in lib/XML/Sig.pm counts the //dsig:Signature elements into $numsigs and iterates over them, but two paths reach next before any digest or key check runs: a SignedInfo/Reference/@URI that resolves to no element while $numsigs is greater than 1, and, when id_attr is set, a reference that does not match the requested ID. The loop records nothing about what it checked, so when every signature takes one of those paths control reaches the unconditional return 1 that ends verify. Two Signature elements whose Reference URI names an ID that no element carries is enough, as is one such element combined with id_attr.

Any caller that passes untrusted XML to verify can receive a true return for a document in which no digest and no signature value was checked; a cert or cert_text trust anchor does not change this, because no key check runs. Versions up to 0.28 use an XML::XPath based verify that has no such skip and are not affected.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
49
EG Risk 49/100

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)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.3% × 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 partial (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: Upgrade to XML::Sig 0.72 or later, which returns false when no reference digest was checked and matched (from the CVE record's solution, CPAN Security Group). Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.3%
EPSS %ILE
25th
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 (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.3% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-06). 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: 14 days if the affected system is publicly exposed; 60 days if it is not.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).

Upgrade to XML::Sig 0.72 or later, which returns false when no reference digest was checked and matched (from the CVE record's solution, CPAN Security Group). Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (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)14 days if the affected system is publicly exposed; 60 days if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (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 3, 2026

Last Modified

October 23, 2026

Advisory Details (3)

Auto-updated Aug 3, 2026
Fix named in the CVE record's solution (CPAN Security Group).

Vendor Advisories for CVE-2026-18568(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 8× in last 7d / 34× 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 255 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 155 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 0.3% · 25th percentile
  2. 2026-11-12 16:33 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  3. 2026-11-11 16:38 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  4. 2026-11-10 16:42 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  5. 2026-11-09 16:34 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  6. 2026-11-08 16:38 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  7. 2026-11-07 16:38 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  8. 2026-11-06 20:40 UTCEchelonGraph re-scored
  9. 2026-11-06 20:40 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  10. 2026-11-06 16:37 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  11. 2026-11-05 16:37 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  12. 2026-11-04 16:35 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  13. 2026-11-03 16:47 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  14. 2026-11-02 16:44 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  15. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  16. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  17. 2026-10-30 21:04 UTCEchelonGraph re-scored
  18. 2026-10-30 21:04 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  19. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  20. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  21. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  22. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  23. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  24. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  25. 2026-10-25 14:45 UTCEchelonGraph re-scored
Show 75 more
  1. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  2. 2026-10-23 21:28 UTCEchelonGraph re-scored
  3. 2026-10-23 21:28 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  4. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  5. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  6. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  7. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  8. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  9. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  10. 2026-10-18 03:58 UTCEchelonGraph re-scored
  11. 2026-10-17 17:50 UTCEchelonGraph re-scored
  12. 2026-10-17 17:49 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  13. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  14. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  15. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  16. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  17. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  18. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  19. 2026-10-12 16:27 UTCEchelonGraph re-scored
  20. 2026-10-11 20:07 UTCEchelonGraph re-scored
  21. 2026-10-11 17:20 UTCEchelonGraph re-scored
  22. 2026-10-11 14:52 UTCEchelonGraph re-scored
  23. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  24. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  25. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  26. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  27. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  28. 2026-10-06 23:46 UTCEchelonGraph re-scored
  29. 2026-10-06 23:46 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  30. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  31. 2026-10-05 19:48 UTCEchelonGraph re-scored
  32. 2026-10-05 19:48 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  33. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  34. 2026-10-04 23:45 UTCEchelonGraph re-scored
  35. 2026-10-04 23:45 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  36. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  37. 2026-10-04 06:19 UTCEchelonGraph re-scored
  38. 2026-10-04 06:19 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  39. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  40. 2026-10-03 02:16 UTCEchelonGraph re-scored
  41. 2026-10-03 02:15 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  42. 2026-10-02 10:19 UTCEchelonGraph re-scored
  43. 2026-10-02 10:18 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  44. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  45. 2026-10-01 15:40 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  46. 2026-10-01 02:33 UTCEchelonGraph re-scored
  47. 2026-10-01 02:33 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  48. 2026-09-30 15:02 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  49. 2026-09-29 15:20 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  50. 2026-09-29 06:41 UTCEchelonGraph re-scored
  51. 2026-09-29 06:41 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  52. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  53. 2026-09-28 07:07 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  54. 2026-09-27 18:15 UTCEchelonGraph re-scored
  55. 2026-09-27 18:15 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  56. 2026-09-27 13:47 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  57. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  58. 2026-09-25 04:47 UTCEchelonGraph re-scored
  59. 2026-09-25 04:47 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  60. 2026-09-24 12:52 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  61. 2026-09-23 23:48 UTCEchelonGraph re-scored
  62. 2026-09-23 23:48 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  63. 2026-09-23 10:18 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  64. 2026-09-22 21:26 UTCEchelonGraph re-scored
  65. 2026-09-22 21:26 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  66. 2026-09-22 05:28 UTCEchelonGraph re-scored
  67. 2026-09-22 05:28 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  68. 2026-09-20 11:05 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  69. 2026-09-19 17:48 UTCEchelonGraph re-scored
  70. 2026-09-19 17:48 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  71. 2026-09-19 03:45 UTCEchelonGraph re-scored
  72. 2026-09-19 03:45 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  73. 2026-09-18 19:27 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  74. 2026-09-18 14:50 UTCGHSA enrichmentGHSA-r3hj-rg3j-262c · GitHub severity HIGH · GitHub CVSS 7.5
  75. 2026-09-18 01:11 UTCEchelonGraph re-scored

Frequently asked(5)

What is CVE-2026-18568?
CVE-2026-18568 is a high-severity vulnerability; its CVE record was published on August 3, 2026. XML::Sig versions from 0.29 before 0.72 for Perl allow signature verification bypass because verify returns true when every signature was skipped before any cryptographic check. verify in lib/XML/Sig.pm counts the //dsig:Signature elements into $numsigs and iterates over them, but two paths reach…
When was the CVE record for CVE-2026-18568 published?
The CVE record for CVE-2026-18568 was published on August 3, 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-2026-18568 actively exploited?
CVE-2026-18568 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (25th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-18568?
CVE-2026-18568 has a CVSS v3.1 base score of 7.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-18568?
The CVE record's solution for CVE-2026-18568, written by its CNA CPAN Security Group, names the fix: "Upgrade to XML::Sig 0.72 or later, which returns false when no reference digest was checked and matched." The vendor advisories EchelonGraph has for CVE-2026-18568 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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