A stack-based out-of-bounds read vulnerability exists in the "s_vlog" function of stunnel, when handling oversized log messages via "vsnprintf". A remote attacker with network access to a stunnel service can send protocol inputs that trigger a log message longer than 1024 bytes, leading to an out-of-bounds stack read and a potential crash. In certain corner cases, the same vulnerability could be used to replace a series of trailing "\n" characters with "\0".
CVE-2026-70368
Score 6.5 from GitHub Security Advisory published 2026-08-04. A secondary CVSS source baseline 6.5; sources differ by 0.0.
- Lower severity and no public exploit yet
A fix is available — apply it.
- CVSS v3
- 6.5
- EG Score
- 6.5MEDIUMmedium confidence
- EG Risk
- 44EG Risk 44/100CISA SSVC
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 computedSeverity65% × 45%Exploitation0% × 40%Automatability100% × 15%CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).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
- 0.4%
- EPSS %ILE
- 36th
- KEV
- Not listed
CISA SSVCTrack 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 none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table
Published
August 4, 2026
Last Modified
August 6, 2026
Advisory Details (2)
Auto-updated Aug 4, 20262462029 – (CVE-2026-70368) CVE-2026-70368 stunnel: Stack-based out-of-bounds read/write in stunnel s_vlog via oversized log message
https://bugzilla.redhat.com/show_bug.cgi?id=2462029CVE-2026-70368 - Red Hat Customer Portal
Affected: Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to a
https://access.redhat.com/security/cve/CVE-2026-70368Vendor Advisories for CVE-2026-70368(2)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(3 across 3 ecosystems)
Debian:12(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| stunnel4 | 3:5.68-2 ... 3:5.78-2 (15 versions) |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| stunnel4 | 3:5.74-2, 3:5.76-1, 3:5.77-1, 3:5.78-1, 3:5.78-2 |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| stunnel | 2:3.26-10 ... 3:5.79-2 (20 versions) |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 17× in last 7d / 71× 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.
Showing the most recent 100 of 167 total refreshes for this CVE.
- 2026-10-04 23:22 UTCEPSS rescore
- 2026-10-04 06:14 UTCEG score recompute
- 2026-10-04 06:14 UTCVendor advisory
- 2026-10-04 06:14 UTCGHSA enrichment
- 2026-10-03 14:26 UTCEPSS rescore
- 2026-10-02 17:56 UTCEPSS rescore
- 2026-10-02 10:12 UTCEG score recompute
- 2026-10-02 10:12 UTCVendor advisory
- 2026-10-02 10:12 UTCGHSA enrichment
- 2026-10-01 19:50 UTCEPSS rescore
- 2026-10-01 02:28 UTCEG score recompute
- 2026-10-01 02:28 UTCVendor advisory
- 2026-10-01 02:28 UTCGHSA enrichment
- 2026-09-30 15:03 UTCEPSS rescore
- 2026-09-29 06:27 UTCEG score recompute
- 2026-09-29 06:27 UTCVendor advisory
- 2026-09-29 06:27 UTCGHSA enrichment
- 2026-09-28 13:52 UTCEPSS rescore
- 2026-09-27 18:05 UTCEG score recompute
- 2026-09-27 18:05 UTCVendor advisory
- 2026-09-27 18:05 UTCGHSA enrichment
- 2026-09-27 13:48 UTCEPSS rescore
- 2026-09-26 15:59 UTCEPSS rescore
- 2026-09-25 04:42 UTCEG score recompute
- 2026-09-25 04:42 UTCGHSA enrichment
Show 75 moreShow fewer
- 2026-09-24 01:48 UTCEG score recompute
- 2026-09-24 01:48 UTCGHSA enrichment
- 2026-09-23 17:54 UTCEPSS rescore
- 2026-09-23 02:37 UTCEG score recompute
- 2026-09-23 02:37 UTCGHSA enrichment
- 2026-09-22 03:27 UTCEG score recompute
- 2026-09-22 03:27 UTCGHSA enrichment
- 2026-09-21 21:09 UTCEPSS rescore
- 2026-09-20 20:16 UTCEPSS rescore
- 2026-09-20 03:21 UTCEG score recompute
- 2026-09-20 03:21 UTCGHSA enrichment
- 2026-09-19 03:41 UTCEG score recompute
- 2026-09-19 03:41 UTCGHSA enrichment
- 2026-09-18 19:28 UTCEPSS rescore
- 2026-09-18 03:36 UTCEG score recompute
- 2026-09-18 03:36 UTCGHSA enrichment
- 2026-09-17 04:26 UTCEG score recompute
- 2026-09-17 04:26 UTCGHSA enrichment
- 2026-09-16 14:08 UTCEPSS rescore
- 2026-09-16 05:16 UTCEG score recompute
- 2026-09-16 05:16 UTCGHSA enrichment
- 2026-09-16 05:15 UTCEPSS rescore
- 2026-09-15 03:12 UTCEPSS rescore
- 2026-09-15 01:45 UTCGHSA enrichment
- 2026-09-14 02:35 UTCEG score recompute
- 2026-09-14 02:35 UTCGHSA enrichment
- 2026-09-13 03:25 UTCEG score recompute
- 2026-09-13 03:25 UTCGHSA enrichment
- 2026-09-12 15:02 UTCEPSS rescore
- 2026-09-12 04:14 UTCEG score recompute
- 2026-09-12 04:14 UTCGHSA enrichment
- 2026-09-11 14:53 UTCEPSS rescore
- 2026-09-11 05:01 UTCEG score recompute
- 2026-09-11 05:01 UTCGHSA enrichment
- 2026-09-10 09:35 UTCEPSS rescore
- 2026-09-10 05:49 UTCGHSA enrichment
- 2026-09-09 06:38 UTCEG score recompute
- 2026-09-09 06:38 UTCGHSA enrichment
- 2026-09-08 22:01 UTCEPSS rescore
- 2026-09-07 18:37 UTCEG score recompute
- 2026-09-07 18:37 UTCGHSA enrichment
- 2026-09-07 16:01 UTCEPSS rescore
- 2026-09-06 13:47 UTCEPSS rescore
- 2026-09-06 08:33 UTCEG score recompute
- 2026-09-06 08:33 UTCGHSA enrichment
- 2026-09-05 15:31 UTCEPSS rescore
- 2026-09-05 09:22 UTCEG score recompute
- 2026-09-05 09:22 UTCGHSA enrichment
- 2026-09-04 10:12 UTCEG score recompute
- 2026-09-04 10:12 UTCGHSA enrichment
- 2026-09-04 05:07 UTCEPSS rescore
- 2026-09-03 08:09 UTCEG score recompute
- 2026-09-03 08:09 UTCGHSA enrichment
- 2026-09-02 14:12 UTCEPSS rescore
- 2026-09-01 22:14 UTCEG score recompute
- 2026-09-01 22:14 UTCGHSA enrichment
- 2026-09-01 13:54 UTCEPSS rescore
- 2026-09-01 04:40 UTCEPSS rescore
- 2026-08-31 23:03 UTCGHSA enrichment
- 2026-08-30 21:00 UTCEG score recompute
- 2026-08-30 21:00 UTCGHSA enrichment
- 2026-08-30 19:17 UTCEPSS rescore
- 2026-08-30 01:22 UTCEPSS rescore
- 2026-08-29 21:49 UTCEG score recompute
- 2026-08-29 21:49 UTCGHSA enrichment
- 2026-08-28 21:42 UTCEPSS rescore
- 2026-08-27 21:47 UTCEG score recompute
- 2026-08-27 21:47 UTCGHSA enrichment
- 2026-08-26 22:37 UTCEG score recompute
- 2026-08-26 22:37 UTCGHSA enrichment
- 2026-08-26 14:47 UTCEPSS rescore
- 2026-08-25 23:26 UTCEG score recompute
- 2026-08-25 23:26 UTCGHSA enrichment
- 2026-08-25 13:49 UTCEPSS rescore
- 2026-08-25 00:15 UTCEG score recompute
Related CVEs(same product + same CWE)
Same product
8 shownDebian:14:stunnel · Debian:12:stunnel4
Frequently asked(5)
What is CVE-2026-70368?
When was CVE-2026-70368 disclosed?
Is CVE-2026-70368 actively exploited?
What is the CVSS score of CVE-2026-70368?
How do I remediate CVE-2026-70368?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-70368
Is Your Infrastructure Affected by CVE-2026-70368?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.