CVE-2026-67422

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 2026-08-07. A secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Elevated

Also known asEUVD-2026-54256 (ENISA EUVD) · GHSA-gm37-52c6-37mw (GitHub Security Advisories) · PYSEC-2026-3654 (OSV.dev)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).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.7%CVSS: 7.5Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

pymdown-extensions is a collection of extensions for the Python Markdown library. In versions up to and including 11.0, four inline processors (caret, tilde, betterem, and magiclink) use regular expressions whose content groups can partition a run of delimiter characters in exponentially many ways, causing catastrophic backtracking. As a result, a single untrusted Markdown line under 50 bytes rendered with markdown.markdown() in each extension's default configuration drives the rendering thread into unbounded CPU usage that grows exponentially with input length, enabling an unauthenticated remote attacker who can submit Markdown to cause denial of service. The exposure is concrete for web applications that render user-supplied Markdown (comments, wikis, issue bodies, live preview), including any app using pymdownx.extra which bundles the vulnerable betterem default, as well as hosted docs/CI systems that build untrusted Markdown. The issue has been fixed in version 11.0.1.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
65
EG Risk 65/100

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.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
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 public PoC (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: A fix is available. Apply it within your standard update timelines 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 (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
0.7% within 30 daysSource: FIRST EPSS. 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).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (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 6, 2026

Last Modified

October 24, 2026

Advisory Details (2)

Auto-updated Aug 6, 2026
Patch available. Sources: github, github_commit.
GitHub commit Patch Available

commit c68498598d7b (facelessuser/pymdown-extensions)

Patch available: facelessuser/pymdown-extensions 11.0.1 (contains commit c68498598d7b)

https://github.com/facelessuser/pymdown-extensions/commit/c68498598d7b13011bb4571350b6e3612a4ce44b
GitHub advisoryMentions a patch (unverified)

pymdown-extensions: exponential-backtracking ReDoS in caret, tilde, betterem, and magiclink inline processors · Advisory · facelessuser/pymdown-extensions · GitHub

Affected: 10.16.1): different extensions, different regexes, and a

https://github.com/facelessuser/pymdown-extensions/security/advisories/GHSA-gm37-52c6-37mw

Patch Availability(4)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatrhdh/rhdh-hub-rhel9:17913114952026-10-08redhat
redhatrhdh/rhdh-hub-rhel9:17895542852026-09-21redhat
redhatansible-automation-platform/bootc-automation-portal-rhel9:17889435312026-09-09redhat
pippymdown-extensions @ 11.0.1 (fixes <= 11.0.0)—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(4 across 4 ecosystems)
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
pymdown-extensions10.11.2-1 ... 9.5-5 (14 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
pymdown-extensions10.13-1 ... 11.0.1-1 (8 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
pymdown-extensions10.13-1 ... 10.19.1-3 (6 versions)
  • every version up to 11.0.1-1: fixed in 11.0.1-1
—
PyPI(1)
PackageVulnerable rangeFix by version rangeDependents
pymdown-extensions1.0.0 ... 9.9.2 (119 versions)
  • every version up to 11.0.1: fixed in 11.0.1
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 36× 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 194 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 94 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-13 16:53 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  2. 2026-11-12 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  3. 2026-11-11 16:40 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  4. 2026-11-10 16:45 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  5. 2026-11-09 16:36 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  6. 2026-11-08 16:40 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  7. 2026-11-07 16:39 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  8. 2026-11-07 15:10 UTCEchelonGraph re-scored
  9. 2026-11-07 15:10 UTCVendor advisory
  10. 2026-11-07 15:10 UTCGHSA enrichmentGHSA-gm37-52c6-37mw · GitHub severity HIGH · GitHub CVSS 7.5
  11. 2026-11-06 16:39 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  12. 2026-11-05 16:38 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  13. 2026-11-04 16:36 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  14. 2026-11-03 16:48 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  15. 2026-11-02 16:45 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  16. 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  17. 2026-11-01 07:40 UTCGHSA enrichmentGHSA-gm37-52c6-37mw · GitHub severity HIGH · GitHub CVSS 7.5
  18. 2026-11-01 07:40 UTCEchelonGraph re-scored
  19. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  20. 2026-10-31 15:49 UTCEchelonGraph re-scored
  21. 2026-10-31 15:49 UTCVendor advisory
  22. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  23. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  24. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  25. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
Show 75 more
  1. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  2. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  3. 2026-10-25 14:10 UTCEchelonGraph re-scored
  4. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  5. 2026-10-23 21:29 UTCEchelonGraph re-scored
  6. 2026-10-23 21:29 UTCVendor advisory
  7. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  8. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  9. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  10. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  11. 2026-10-20 09:45 UTCEchelonGraph re-scored
  12. 2026-10-20 09:45 UTCVendor advisory
  13. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  14. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  15. 2026-10-18 03:20 UTCEchelonGraph re-scored
  16. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  17. 2026-10-16 16:43 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  18. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  19. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  20. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  21. 2026-10-13 10:23 UTCEchelonGraph re-scored
  22. 2026-10-13 10:23 UTCVendor advisory
  23. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  24. 2026-10-12 15:45 UTCEchelonGraph re-scored
  25. 2026-10-11 19:30 UTCEchelonGraph re-scored
  26. 2026-10-11 16:46 UTCEchelonGraph re-scored
  27. 2026-10-11 14:06 UTCEchelonGraph re-scored
  28. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  29. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  30. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  31. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  32. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  33. 2026-10-06 23:23 UTCEchelonGraph re-scored
  34. 2026-10-06 23:23 UTCVendor advisory
  35. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  36. 2026-10-05 18:37 UTCEchelonGraph re-scored
  37. 2026-10-05 18:37 UTCVendor advisory
  38. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  39. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  40. 2026-10-04 23:21 UTCVendor advisory
  41. 2026-10-04 05:48 UTCEchelonGraph re-scored
  42. 2026-10-04 05:48 UTCVendor advisory
  43. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  44. 2026-10-03 01:03 UTCEchelonGraph re-scored
  45. 2026-10-03 01:03 UTCVendor advisory
  46. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  47. 2026-10-02 09:37 UTCEchelonGraph re-scored
  48. 2026-10-02 09:37 UTCVendor advisory
  49. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  50. 2026-10-01 12:11 UTCVendor advisory
  51. 2026-09-30 23:00 UTCEchelonGraph re-scored
  52. 2026-09-30 23:00 UTCVendor advisory
  53. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  54. 2026-09-29 05:52 UTCEchelonGraph re-scored
  55. 2026-09-29 05:52 UTCVendor advisory
  56. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  57. 2026-09-28 06:35 UTCVendor advisory
  58. 2026-09-27 17:28 UTCEchelonGraph re-scored
  59. 2026-09-27 17:28 UTCVendor advisory
  60. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  61. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  62. 2026-09-25 04:20 UTCEchelonGraph re-scored
  63. 2026-09-25 04:20 UTCVendor advisory
  64. 2026-09-24 10:25 UTCVendor advisory
  65. 2026-09-23 21:17 UTCEchelonGraph re-scored
  66. 2026-09-23 21:17 UTCVendor advisory
  67. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.7% · 49th percentile
  68. 2026-09-23 04:14 UTCEchelonGraph re-scored
  69. 2026-09-23 04:14 UTCVendor advisory
  70. 2026-09-22 15:06 UTCVendor advisory
  71. 2026-09-22 01:53 UTCEchelonGraph re-scored
  72. 2026-09-22 01:53 UTCVendor advisory
  73. 2026-09-21 12:45 UTCEchelonGraph re-scored
  74. 2026-09-21 12:45 UTCVendor advisory
  75. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.7% · 49th percentile

Frequently asked(5)

What is CVE-2026-67422?
CVE-2026-67422 is a high-severity vulnerability; its CVE record was published on August 6, 2026. pymdown-extensions is a collection of extensions for the Python Markdown library. In versions up to and including 11.0, four inline processors (caret, tilde, betterem, and magiclink) use regular expressions whose content groups can partition a run of delimiter characters in exponentially many ways,…
When was the CVE record for CVE-2026-67422 published?
The CVE record for CVE-2026-67422 was published on August 6, 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 24, 2026; the record at its source may have been updated since.
Is CVE-2026-67422 actively exploited?
CVE-2026-67422 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-2026-67422?
CVE-2026-67422 has a CVSS base score of 7.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-67422?
A fix for CVE-2026-67422 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-67422 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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