CVE-2026-3548
Buffer overflow in CRL number parsing in wolfSSL
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.2
Buffer overflow in CRL number parsing in wolfSSL
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
- Record
CVE-2026-3548- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U - Weakness
- CWE-787, CWE-122
- Updated
- 2026-11-02
EUVDEUVD-2026-13150
7.2
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
- Record
EUVD-2026-13150- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-86fv-q5vx-mw5m
7.2
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a...
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
- Record
GHSA-86fv-q5vx-mw5m- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/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 - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-122, CWE-787
- Updated
- 2026-11-02
NVD
7.2
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
- Record
CVE-2026-3548- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/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 - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-122, CWE-787
- Updated
- 2026-11-02
OSVALPINE-CVE-2026-3548
9.8
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
- Record
ALPINE-CVE-2026-3548- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-03
OSV
7.2
Buffer overflow in CRL number parsing in wolfSSL
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
- Record
CVE-2026-3548- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U - Weakness
- CWE-122, CWE-787
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-3548
9.8
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
- Record
DEBIAN-CVE-2026-3548- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVJLSEC-2026-707
7.2
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a...
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
- Record
JLSEC-2026-707- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/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 - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-3548
7.2
Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.
- Record
UBUNTU-CVE-2026-3548- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
wolfsslAlpine:v3.23 |
before 5.9.1-r0 | 5.9.1-r0 |
wolfsslAlpine:v3.24 |
before 5.9.0-r0 | 5.9.0-r0 |
wolfsslDebian:12 |
All versions, plus listed versions 5.5.4-25.5.4-2+deb12u15.5.4-2+deb12u25.5.4-2+deb12u35.5.4-2.1 Show 22 moreShow less5.6.4-15.6.4-25.6.6-15.6.6-1.15.6.6-1.25.6.6-1.35.6.6-1.3~exp15.7.0-0.15.7.0-0.25.7.0-0.35.7.2-0.15.7.2-0.25.7.2-0.35.7.2-0.45.8.2-15.8.2-1.15.8.2-1.25.8.4-15.9.0-0.15.9.0-0.25.9.1-0.15.9.2-1 |
None known |
wolfsslDebian:13 |
All versions, plus listed versions 5.7.2-0.15.7.2-0.1+deb13u15.7.2-0.1+deb13u25.7.2-0.25.7.2-0.3 Show 9 moreShow less5.7.2-0.45.8.2-15.8.2-1.15.8.2-1.25.8.4-15.9.0-0.15.9.0-0.25.9.1-0.15.9.2-1 |
None known |
wolfSSL_jllJulia |
before 5.9.2+0 | 5.9.2+0 |
wolfsslUbuntu:16.04:LTS |
All versions, plus listed versions 3.4.8+dfsg-1 |
None known |
wolfsslUbuntu:18.04:LTS |
All versions, plus listed versions 3.10.2+dfsg-23.12.0+dfsg-13.12.2+dfsg-13.13.0+dfsg-1 |
None known |
wolfsslUbuntu:20.04:LTS |
All versions, plus listed versions 4.1.0+dfsg-24.2.0+dfsg-14.2.0+dfsg-24.2.0+dfsg-34.3.0+dfsg-2 |
None known |
wolfsslUbuntu:22.04:LTS |
All versions, plus listed versions 4.6.0-35.0.0-15.1.1-15.2.0-15.2.0-2 |
None known |
wolfsslUbuntu:24.04:LTS |
All versions, plus listed versions 5.5.4-25.5.4-2.15.6.4-25.6.6-1.25.6.6-1.35.6.6-1.3build1 |
None known |
wolfsslUbuntu:25.10 |
All versions, plus listed versions 5.7.2-0.1 |
None known |
wolfsslUbuntu:26.10 |
All versions, plus listed versions 5.9.1-0.15.9.2-1 |
None known |
wolfsslUbuntu:26.04:LTS |
All versions, plus listed versions 5.7.2-0.15.8.2-1.25.8.4-15.9.1-0.1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, aliases, references | OSV | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-3548 is a high vulnerability (CVSS 7.2) in Wolfssl, published March 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.50%, the 43rd percentile. Fixed in wolfssl 5.9.1-r0.