Security Vulnerabilities
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the BER decoder shared by the CER and DER codecs parses long-form tags by accumulating continuation octets without an upper bound on the tag ID size, allowing a crafted input to force construction of an arbitrarily large integer with CPU cost growing quadratically and to trigger unhandled ValueError exceptions in Python 3.11+ error formatting paths. Any application decoding untrusted BER, CER, or DER input is affected. This issue is fixed in version 0.6.4.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-07-14
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the BER, CER, and DER decoders process OBJECT IDENTIFIER and RELATIVE-OID values in quadratic time relative to the number of arcs, so a small crafted payload containing an OID with many arcs consumes excessive CPU per decode() call and can deny service to applications that decode untrusted ASN.1 data. The corresponding encoders have the same quadratic behavior when an application re-encodes previously decoded attacker-supplied values. This issue is fixed in version 0.6.4.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-07-14
Out-of-bounds read in Microsoft Graphics Component allows an unauthorized attacker to execute code locally.
CVSS Score
7.8
EPSS Score
0.003
Published
2026-07-14
Heap-based buffer overflow in Microsoft Windows Media Foundation allows an unauthorized attacker to execute code locally.
CVSS Score
7.8
EPSS Score
0.003
Published
2026-07-14
Out-of-bounds read in Windows Kernel allows an authorized attacker to bypass a security feature locally.
CVSS Score
5.5
EPSS Score
0.003
Published
2026-07-14
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
CVSS Score
7.8
EPSS Score
0.003
Published
2026-07-14
Improper authorization in Windows Admin Center allows an authorized attacker to execute code locally.
CVSS Score
7.8
EPSS Score
0.003
Published
2026-07-14
Improper neutralization of special elements used in a command ('command injection') in Windows Narrator Braille allows an authorized attacker to elevate privileges locally.
CVSS Score
7.8
EPSS Score
0.004
Published
2026-07-14
Improper link resolution before file access ('link following') in Window PC Manager allows an authorized attacker to elevate privileges locally.
CVSS Score
7.8
EPSS Score
0.003
Published
2026-07-14
Missing authorization in Azure CycleCloud allows an authorized attacker to elevate privileges over a network.
CVSS Score
6.5
EPSS Score
0.004
Published
2026-07-14