5.4

CVE-2026-5392: wolfSSL heap OOB read in PKCS7 SignedData streaming

Analyzed
AliasesUBUNTU-CVE-2026-5392DEBIAN-CVE-2026-5392ALPINE-CVE-2026-5392
Published 09-04-2026Last modified 10-04-2026

Vulnerability summary

CVE-2026-5392 is a medium (CVSS 5.4) Out-of-bounds Read vulnerability in wolfssl. EPSS estimates a 0.16% chance of exploitation in the next 30 days, higher than 5% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 2.3, adjacent network); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.4/10
010
Medium · v3.1 (NVD)
EPSS score
0.16%
0%100%
Low · -0.08 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 09-04-2026
    PublishedVulnerability first disclosed.
  2. 10-04-2026
    Last modifiedVulnerability information updated.

Description

Heap out-of-bounds read in PKCS7 parsing. A crafted PKCS7 message can trigger an OOB read on the heap. The missing bounds check is in the indefinite-length end-of-content verification loop in PKCS7_VerifySignedData().

CVSS metrics

7 scores · 5 sources · 2 versions

EPSS trend

Probability

0.16%

Chance of exploitation in the next 30 days

Percentile

5%

Versus all other CVEs

30-day change

Decrease -0.08 pp

From 0.24% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: adjacent network, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Alpine1 product
  • wolfssl< 5.9.1-r0
Debian1 product
  • wolfsslAll versions (No fix recorded)
Ubuntu1 product
  • wolfsslAll versions (No fix recorded)
Wolfssl1 product

4 vendors · 4 products

References

5 links