CVE-2026-6791

MEDIUMPre-NVD 6.66.6—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.6 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 89% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 4 sources updated this week
6.6EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.6Exploit: None knownExposed: 0

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
6.6(medium)
EG Risk
30(Track)
EG Risk 30/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity66% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
11%
KEV
Not listed

Published

August 10, 2026

Last Modified

August 12, 2026

Advisory Details (1)

Auto-updated Aug 10, 2026
No patch confirmed yet.
generic

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(2)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
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.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 27× in last 7d / 40× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.

  1. 2026-08-20 22:56 UTCEPSS rescore
  2. 2026-08-20 06:27 UTCEG score recompute
  3. 2026-08-20 06:27 UTCVendor advisory
  4. 2026-08-20 06:27 UTCGHSA enrichment
  5. 2026-08-19 17:04 UTCEPSS rescore
  6. 2026-08-19 04:46 UTCEG score recompute
  7. 2026-08-19 04:46 UTCVendor advisory
  8. 2026-08-19 04:46 UTCGHSA enrichment
  9. 2026-08-18 13:49 UTCEPSS rescore
  10. 2026-08-18 13:49 UTCEPSS rescore
  11. 2026-08-18 03:06 UTCEG score recompute
  12. 2026-08-18 03:06 UTCVendor advisory
  13. 2026-08-18 03:06 UTCGHSA enrichment
  14. 2026-08-17 13:47 UTCEPSS rescore
  15. 2026-08-17 01:25 UTCEG score recompute
  16. 2026-08-17 01:25 UTCVendor advisory
  17. 2026-08-17 01:25 UTCGHSA enrichment
  18. 2026-08-16 14:56 UTCEPSS rescore
  19. 2026-08-16 14:56 UTCEPSS rescore
  20. 2026-08-16 02:15 UTCEPSS rescore
  21. 2026-08-15 23:45 UTCEG score recompute
  22. 2026-08-15 23:45 UTCVendor advisory
  23. 2026-08-15 23:45 UTCGHSA enrichment
  24. 2026-08-15 01:31 UTCEPSS rescore
  25. 2026-08-14 22:04 UTCEG score recompute
Show 15 more
  1. 2026-08-14 22:04 UTCVendor advisory
  2. 2026-08-14 22:04 UTCGHSA enrichment
  3. 2026-08-13 22:00 UTCEPSS rescore
  4. 2026-08-13 20:18 UTCVendor advisory
  5. 2026-08-13 20:18 UTCGHSA enrichment
  6. 2026-08-12 18:38 UTCEG score recompute
  7. 2026-08-12 18:38 UTCGHSA enrichment
  8. 2026-08-12 18:17 UTCEG score recompute
  9. 2026-08-12 18:17 UTCGHSA enrichment
  10. 2026-08-12 13:51 UTCEPSS rescore
  11. 2026-08-11 21:07 UTCEG score recompute
  12. 2026-08-11 21:07 UTCGHSA enrichment
  13. 2026-08-10 19:27 UTCEG score recompute
  14. 2026-08-10 18:55 UTCEG score recompute
  15. 2026-08-10 18:54 UTCMITRE cvelistV5first tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-6791?
CVE-2026-6791 is a medium vulnerability 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 CVE-2026-6791 disclosed?
CVE-2026-6791 was first published in the National Vulnerability Database on August 10, 2026, with the most recent update on August 12, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-6791 actively exploited?
CVE-2026-6791 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 88.8% of all scored CVEs.
What is the CVSS score of CVE-2026-6791?
CVE-2026-6791 has a CVSS v3 base score of 6.6 (NVD).
How do I remediate CVE-2026-6791?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-6791, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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