CVE-2026-6791

MEDIUMPre-NVD 6.66.6
EchelonGraph scoreMEDIUM confidence

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

This medium-severity CVE scores 6.6 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2% (12th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source
Trending — 4 sources updated this week

Also known asEUVD-2026-55729 (ENISA EUVD) · GHSA-ch73-g8qv-r6r5 (GitHub Security Advisories)Source: ENISA EUVD

6.6EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 6.6Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

When expanding paths that begin with a tilde (~) followed by a username, the internal parse_tilde function extracts the username to determine the user's home directory. The implementation allocates memory for this username directly on the stack using the strndupa macro. Because the size of this allocation was determined by the length of the user-supplied input without any bounds checks, passing an excessively long username e.g. thousands of characters, forces the thread to exhaust its stack space. Thus if an application passes untrusted, attacker-controlled input to the wordexp function, an attacker can trigger a stack clash.

CVSS v3
6.6
EG Score
6.6MEDIUMmedium confidence
EG Risk
30
EG Risk 30/100

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)
Severity66% × 45%
Impact severity (EG Severity): CVSS 6.6 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.2% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (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.
EPSS PROB
0.2%
EPSS %ILE
12th
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 (6.6): severity, escalated by confirmed exploitation. This CVE's 6.6 is its impact severity (EG Severity), not escalated.

EG Severity
6.6 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-29). 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 every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade 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 every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (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)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (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 10, 2026

Last Modified

October 24, 2026

Advisory Details (1)

Auto-updated Aug 10, 2026
Patch available.
Web page

34091 – (CVE-2026-6791) wordepx: unbounded alloca (strndupa) in parse_tilde

https://sourceware.org/bugzilla/show_bug.cgi?id=34091

Vendor Advisories for CVE-2026-6791(7)

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

Patch Availability(7)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntunscd (2.43-2ubuntu2.4) @ resolute2026-10-29ubuntu
ubuntunscd (2.39-0ubuntu8.9) @ noble2026-10-29ubuntu
redhatrhui5/rhua-rhel9:17919786932026-10-14redhat
redhatglibc-0:2.34-283.el9_82026-10-08redhat
redhatglibc-0:2.39-142.el10_22026-10-08redhat
redhatglibc-0:2.28-251.el8_10.432026-10-07redhat
redhatglibc-main-2.43-8.1.hum12026-08-10redhat

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

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
glibc2.36-10~0 ... 2.44-2 (134 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
glibc2.41-12 ... 2.44-2 (40 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
glibc2.41-12 ... 2.43-2 (27 versions)
  • every version up to 2.43-3: fixed in 2.43-3
—

Weakness Classification(1)

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

Additional Vendor Advisories

(2)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 10× in last 7d / 56× 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 it from the CNA feed. 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). Most recent first.

Showing the most recent 100 of 230 refreshes 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 130 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  2. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  3. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  4. 2026-10-29 16:57 UTCEG score recompute
  5. 2026-10-29 16:57 UTCVendor advisory
  6. 2026-10-29 16:57 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  7. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  8. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  9. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  10. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  11. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  12. 2026-10-25 14:10 UTCEG score recompute
  13. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  14. 2026-10-24 16:29 UTCVendor advisory
  15. 2026-10-24 16:29 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  16. 2026-10-23 19:33 UTCEG score recompute
  17. 2026-10-23 19:33 UTCVendor advisory
  18. 2026-10-23 19:33 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  19. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  20. 2026-10-22 19:33 UTCEG score recompute
  21. 2026-10-22 19:33 UTCVendor advisory
  22. 2026-10-22 19:33 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  23. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  24. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  25. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
Show 75 more
  1. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  2. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  3. 2026-10-18 03:20 UTCEG score recompute
  4. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  5. 2026-10-16 16:43 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  6. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  7. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  8. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  9. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  10. 2026-10-12 15:45 UTCEG score recompute
  11. 2026-10-11 19:30 UTCEG score recompute
  12. 2026-10-11 16:45 UTCEG score recompute
  13. 2026-10-11 14:06 UTCEG score recompute
  14. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  15. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  16. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  17. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  18. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  19. 2026-10-06 18:20 UTCEG score recompute
  20. 2026-10-06 18:20 UTCVendor advisory
  21. 2026-10-06 18:20 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  22. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  23. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  24. 2026-10-05 07:45 UTCEG score recompute
  25. 2026-10-05 07:45 UTCVendor advisory
  26. 2026-10-05 07:45 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  27. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  28. 2026-10-04 04:18 UTCEG score recompute
  29. 2026-10-04 04:18 UTCVendor advisory
  30. 2026-10-04 04:18 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  31. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  32. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  33. 2026-10-02 09:18 UTCEG score recompute
  34. 2026-10-02 09:18 UTCVendor advisory
  35. 2026-10-02 09:18 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  36. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  37. 2026-09-30 22:25 UTCEG score recompute
  38. 2026-09-30 22:25 UTCVendor advisory
  39. 2026-09-30 22:25 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  40. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  41. 2026-09-29 05:22 UTCEG score recompute
  42. 2026-09-29 05:22 UTCVendor advisory
  43. 2026-09-29 05:21 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  44. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  45. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  46. 2026-09-27 12:36 UTCEG score recompute
  47. 2026-09-27 12:36 UTCVendor advisory
  48. 2026-09-27 12:36 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  49. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  50. 2026-09-25 04:00 UTCEG score recompute
  51. 2026-09-25 04:00 UTCVendor advisory
  52. 2026-09-25 04:00 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  53. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  54. 2026-09-23 14:31 UTCEG score recompute
  55. 2026-09-23 14:31 UTCVendor advisory
  56. 2026-09-23 14:31 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  57. 2026-09-22 12:49 UTCEG score recompute
  58. 2026-09-22 12:49 UTCVendor advisory
  59. 2026-09-22 12:49 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  60. 2026-09-21 21:09 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  61. 2026-09-21 11:08 UTCEG score recompute
  62. 2026-09-21 11:08 UTCVendor advisory
  63. 2026-09-21 11:08 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  64. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  65. 2026-09-20 05:45 UTCEG score recompute
  66. 2026-09-20 05:45 UTCVendor advisory
  67. 2026-09-20 05:45 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  68. 2026-09-19 04:04 UTCEG score recompute
  69. 2026-09-19 04:04 UTCVendor advisory
  70. 2026-09-19 04:04 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  71. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  72. 2026-09-18 02:23 UTCEG score recompute
  73. 2026-09-18 02:23 UTCVendor advisory
  74. 2026-09-18 02:23 UTCGHSA enrichmentGHSA-ch73-g8qv-r6r5
  75. 2026-09-17 00:43 UTCEG score recompute

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-6791?
CVE-2026-6791 is a medium-severity vulnerability; its CVE record was published on August 10, 2026. When expanding paths that begin with a tilde (~) followed by a username, the internal parse_tilde function extracts the username to determine the user's home directory. The implementation allocates memory for this username directly on the stack using the strndupa macro. Because the size of this…
When was the CVE record for CVE-2026-6791 published?
The CVE record for CVE-2026-6791 was published on August 10, 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-2026-6791 actively exploited?
CVE-2026-6791 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (12th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-6791?
CVE-2026-6791 has a CVSS base score of 6.6 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-6791?
A fix for CVE-2026-6791 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-6791 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-6791

Explore →

Is Your Infrastructure Affected by CVE-2026-6791?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs