Issue summary: PBMAC1 parameters in PKCS#12 files are missing validation
which can trigger a stack-based buffer overflow, invalid pointer or NULL
pointer dereference during MAC verification.
Impact summary: The stack buffer overflow or NULL pointer dereference may
cause a crash leading to Denial of Service for an application that parses
untrusted PKCS#12 files. The buffer overflow may also potentially enable
code execution depending on platform mitigations.
When verifying a PKCS#12 file that uses PBMAC1 for the MAC, the PBKDF2
salt and keylength parameters from the file are used without validation.
If the value of keylength exceeds the size of the fixed stack buffer used
for the derived key (64 bytes), the key derivation will overflow the buffer.
The overflow length is attacker-controlled. Also, if the salt parameter is
not an OCTET STRING type this can lead to invalid or NULL pointer
dereference.
Exploiting this issue requires a user or application to process
a maliciously crafted PKCS#12 file. It is uncommon to accept untrusted
PKCS#12 files in applications as they are usually used to store private
keys which are trusted by definition. For this reason the issue was assessed
as Moderate severity.
The FIPS modules in 3.6, 3.5 and 3.4 are not affected by this issue, as
PKCS#12 processing is outside the OpenSSL FIPS module boundary.
OpenSSL 3.6, 3.5 and 3.4 are vulnerable to this issue.
OpenSSL 3.3, 3.0, 1.1.1 and 1.0.2 are not affected by this issue as they do
not support PBMAC1 in PKCS#12.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (6.1): severity, escalated by confirmed exploitation. This CVE's 6.1 is its impact severity (EG Severity), not escalated.
- EG Severity
- 6.1 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 5.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-25). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it