CVE-2026-6678: Integer underflow in wc_PKCS7_DecryptOri handling crafted Other Recipient Info
Vulnerability summary
CVE-2026-6678 is a medium (CVSS 5.3) Integer Underflow (Wrap or Wraparound) vulnerability in wolfssl. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 26.1% of scored vulnerabilities.
Not severe (CVSS 1, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Timeline
- 25-06-2026PublishedVulnerability first disclosed.
- 01-07-2026Last modifiedVulnerability information updated.
Description
Integer underflow in wc_PKCS7_DecryptOri when handling crafted Other Recipient Info, leading to incorrect length handling during decryption.
CVSS metrics
7 scores · 5 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated1.0LowCVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/U:Clear
- NVDNIST1.0LowCVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/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:Clear
- OSV · UbuntuEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- OSV · DebianEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- OSV · AlpineEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS trend
Probability
0.33%
Chance of exploitation in the next 30 days
Percentile
26%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.33% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, low-privilege account, user interaction (CVSS vector). Other conditions: not stated in public data.
Alpine1 product
- wolfssl≥ 3.15.5, < 5.9.2-r0
Debian1 product
- wolfssl< 5.5.4-2+deb12u3 | < 5.7.2-0.1+deb13u2
Ubuntu1 product
- wolfsslAll versions (No fix recorded)
Wolfssl1 product
- wolfssl≥ 3.15.5, ≤ 5.9.1 | ≥ 3.15.5, < 5.9.2
4 vendors · 4 products
