CVE-2026-83742

HIGHNVD 8.88.8
EchelonGraph scoreHIGH confidence

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

Score 8.8 from GitHub Security Advisory published 2026-10-07. NVD baseline CVSS 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 3 sources updated this week

Also known asEUVD-2026-94164 (ENISA EUVD) · GHSA-4ff8-whrv-3wcm (GitHub Security Advisories)Source: ENISA EUVD

8.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 8.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Unsigned integer underflow in wstrncat() in src/port.c in wolfSSL wolfSSH from v1.4.11 through v1.5.0 on non-Windows platforms allows an authenticated remote attacker to write one out-of-bounds null byte past the end of a stack buffer by sending a crafted SFTP path. wolfSSH_RealPath() in src/ssh.c appends each path component with a remaining-size bound (outSz - curSz) rather than the full destination size, so once the accumulated path reaches half the output buffer the size_t computation n - strlen(s1) - 1 wraps to near SIZE_MAX. The strncat() call is then effectively unbounded and copies the whole component; when that component exactly fills the remainder of the buffer, its terminating null is written one byte past the end. The caller's own length check keeps the copied data inside the buffer, so the overflow is limited to that single null byte, which may corrupt an adjacent stack value and crash the process. Applications that call the public wolfSSH_RealPath() with an output buffer smaller than the input path are additionally exposed to an unbounded copy, because the word32 expression outSz - segSz in that length check also wraps.

CVSS v3
8.8
EG Score
8.8HIGHhigh confidence
EG Risk
40
EG Risk 40/100

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)
Severity88% × 45%
Impact severity (EG Severity): CVSS 8.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.4% × 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
0.4%
EPSS %ILE
37th
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 (8.8): severity, escalated by confirmed exploitation. This CVE's 8.8 is its impact severity (EG Severity), not escalated.

EG Severity
8.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-27). 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

October 7, 2026

Last Modified

October 13, 2026

Advisory Details (4)

Auto-updated Oct 7, 2026
Patch available. Sources: github_pr, github_commit.
GitHub commit Patch Available

commit fbc7cd88a23b (wolfSSL/wolfssh)

Patch available: wolfSSL/wolfssh v1.6.0-stable (contains commit fbc7cd88a23b)

https://github.com/wolfSSL/wolfssh/commit/fbc7cd88a23b59a45a584020a4c7242d9bd70f35
GitHub commit Patch Available

commit 513e52b18927 (wolfSSL/wolfssh)

Patch available: wolfSSL/wolfssh v1.6.0-stable (contains commit 513e52b18927)

https://github.com/wolfSSL/wolfssh/commit/513e52b18927a4e3f7cf17ecaf107958e56139de
GitHub commit Patch Available

commit 822e4464560b (wolfSSL/wolfssh)

Patch available: wolfSSL/wolfssh v1.6.0-stable (contains commit 822e4464560b)

https://github.com/wolfSSL/wolfssh/commit/822e4464560b467580ea37a2fc03b0988d88b71f
GitHub pull request Patch Available

Fix multiple reported issues

Patch available: wolfSSL/wolfssh v1.6.0-stable (PR #1084 merged 2026-07-16)

https://github.com/wolfSSL/wolfssh/pull/1084

Vendor Advisories for CVE-2026-83742(1)

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

Weakness Classification(3)

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

Data Freshness Timeline

(refreshed 9× 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.

  1. 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  2. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  3. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  4. 2026-10-29 16:34 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  5. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  6. 2026-10-27 21:10 UTCEG score recompute
  7. 2026-10-27 21:10 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm · GitHub CVSS 8.8
  8. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  9. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  10. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  11. 2026-10-25 13:56 UTCEG score recompute
  12. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  13. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  14. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  15. 2026-10-21 16:34 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  16. 2026-10-20 18:02 UTCEG score recompute
  17. 2026-10-20 18:02 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm · GitHub CVSS 8.8
  18. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  19. 2026-10-19 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  20. 2026-10-18 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  21. 2026-10-18 03:07 UTCEG score recompute
  22. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  23. 2026-10-16 16:44 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  24. 2026-10-15 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  25. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
Show 31 more
  1. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  2. 2026-10-13 14:47 UTCEG score recompute▲ 3.50
  3. 2026-10-13 14:46 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm
  4. 2026-10-13 14:44 UTCNVD updateCVSS v3 → 8.8 · severity → HIGH
  5. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  6. 2026-10-12 14:54 UTCEG score recompute
  7. 2026-10-11 19:19 UTCEG score recompute
  8. 2026-10-11 16:35 UTCEG score recompute
  9. 2026-10-11 13:53 UTCEG score recompute
  10. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  11. 2026-10-11 12:32 UTCEG score recompute
  12. 2026-10-11 12:32 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm
  13. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  14. 2026-10-10 13:29 UTCEG score recompute
  15. 2026-10-10 13:29 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm
  16. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  17. 2026-10-09 14:24 UTCEG score recompute
  18. 2026-10-09 14:24 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm
  19. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  20. 2026-10-08 15:18 UTCEG score recompute
  21. 2026-10-08 15:18 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm
  22. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  23. 2026-10-07 16:15 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm
  24. 2026-10-07 12:21 UTCEG score recompute
  25. 2026-10-07 12:21 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm
  26. 2026-10-07 11:38 UTCEG score recompute
  27. 2026-10-07 11:37 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm
  28. 2026-10-07 03:31 UTCEG score recompute
  29. 2026-10-07 03:31 UTCGHSA enrichmentGHSA-4ff8-whrv-3wcm
  30. 2026-10-07 03:02 UTCEG score recomputeFirst assessed: 5.3 MEDIUM
  31. 2026-10-07 03:01 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-83742?
CVE-2026-83742 is a high-severity vulnerability; its CVE record was published on October 7, 2026. Unsigned integer underflow in wstrncat() in src/port.c in wolfSSL wolfSSH from v1.4.11 through v1.5.0 on non-Windows platforms allows an authenticated remote attacker to write one out-of-bounds null byte past the end of a stack buffer by sending a crafted SFTP path. wolfSSH_RealPath() in src/ssh.c…
When was the CVE record for CVE-2026-83742 published?
The CVE record for CVE-2026-83742 was published on October 7, 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 13, 2026; the record at its source may have been updated since.
Is CVE-2026-83742 actively exploited?
CVE-2026-83742 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (37th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-83742?
CVE-2026-83742 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2026-83742?
A fix for CVE-2026-83742 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-83742 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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