CVE-2026-5392: wolfSSL heap OOB read in PKCS7 SignedData streaming
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.
Not severe (CVSS 2.3, adjacent network); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Timeline
- 09-04-2026PublishedVulnerability first disclosed.
- 10-04-2026Last 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- OSV · UbuntuEcosystem advisory · calculated2.3LowCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
- NVDNIST2.3LowCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated5.4MediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
- OSV · DebianEcosystem advisory · calculated5.4MediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
- OSV · AlpineEcosystem advisory · calculated5.4MediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
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
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
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
- wolfssl< 5.9.1
4 vendors · 4 products