CVE-2026-17510: Crypt::OpenSSL::PKCS12 versions before 1.98 for Perl allow a NULL pointer dereference in print_attribute via a zero length BMPSTRING attribute

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-09 · updated 2026-10-23
Weakness: CWE-476

Description

Crypt::OpenSSL::PKCS12 versions before 1.98 for Perl allow a NULL pointer dereference in print_attribute via a zero length BMPSTRING attribute. print_attribute() sizes the destination buffer for a BMPSTRING attribute from its declared byte length with `Renew(*attribute, length, char)`. A zero length attribute makes that a zero size reallocation, which Perl implements as a free returning NULL, so the buffer pointer becomes NULL, the following `strncpy` copies nothing, and the caller dereferences NULL in the `strlen()` it passes to `newSVpvn()`. A zero length BMPSTRING is even length, so the ASN.1 decoder accepts it and the value reaches this code. The UTF8STRING, OCTET STRING and BIT STRING arms size on `length + 1` or `length * 4 + 1` and are unaffected. Any caller that passes an untrusted PKCS#12 file to info_as_hash() can crash the process. info() prints attribute values directly without sizing a buffer and is unaffected.

Affected products

JONASBN Crypt::OpenSSL::PKCS12: before 1.98 — fixed in 1.98

How to fix

Upgrade to a fixed version: JONASBN Crypt::OpenSSL::PKCS12 1.98. Check the vendor advisory for mitigations.

References

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