CVE-2026-93599

See a problem?
Please try reporting it to the source first.
Source
https://cve.org/CVERecord?id=CVE-2026-93599
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93599.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-93599
Aliases
Downstream
Published
2026-09-18T13:20:10Z
Modified
2026-09-19T03:55:33Z
Severity
  • 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
rustls-webpki before 0.103.13 Panic via empty BIT STRING
Details

rustls-webpki through 0.103.12 (and 0.104.0-alpha releases before 0.104.0-alpha.7) contains a reachable panic in bit_string_flags() in src/der.rs. The input guard fails to reject a named-bit BIT STRING whose content is exactly [0x00] (zero padding bits and no data bytes), so raw_bits.len() - 1 underflows on the empty slice and the subsequent index operation panics (subtract-with-overflow in debug, index-out-of-bounds in release). The condition is reachable through the public API BorrowedCertRevocationList::from_der() when a CRL contains an issuingDistributionPoint extension with such an onlySomeReasons value. Exploitation requires an application that explicitly opts in to CRL revocation checking by passing RevocationOptions to verify_for_usage() and that parses CRL bytes obtained from a source the attacker can influence; the default rustls configuration, which does not use RevocationOptions, is unaffected. A crafted CRL causes a denial of service via the panic. Fixed in 0.103.13 and 0.104.0-alpha.7.

Database specific 
{
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
        "CWE-191"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93599.json"
}
References

Affected packages

Git / github.com/rustls/webpki

Affected ranges

Type
GIT
Repo
https://github.com/rustls/webpki
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
2879b2ce7a476181ac3050f73fe0835f04728e86
Introduced
5a23b7e1c7b6e898d6bb437730a029b2695aa3eb
Fixed
d3b9a6db1e3b7a81ca1e1e6136a303f4ab11b32d
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "0.103.13"
        },
        {
            "introduced": "0.104.0-alpha.1"
        },
        {
            "fixed": "0.104.0-alpha.7"
        }
    ],
    "source": "AFFECTED_FIELD"
}

Affected versions

0.*
0.10.0
0.10.1
0.10.2
0.11.0
0.12.1
0.13.0
0.16.0
0.17.0
0.9.4
v/0.*
v/0.100.0
v/0.100.0-alpha.1
v/0.100.0-alpha.2
v/0.100.1
v/0.101.2
v/0.102.0
v/0.102.0-alpha.0
v/0.102.0-alpha.2
v/0.102.0-alpha.4
v/0.102.0-alpha.6
v/0.102.0-alpha.8
v/0.102.1
v/0.102.2
v/0.102.3
v/0.102.4
v/0.102.5
v/0.102.6
v/0.102.7
v/0.102.8
v/0.103.0
v/0.103.1
v/0.103.10
v/0.103.11
v/0.103.12
v/0.103.2
v/0.103.3
v/0.103.4
v/0.103.5
v/0.103.6
v/0.103.7
v/0.103.8
v/0.103.9
v/0.104.0-alpha.1
v/0.104.0-alpha.2
v/0.104.0-alpha.3
v/0.104.0-alpha.4
v/0.104.0-alpha.5
v/0.104.0-alpha.6

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93599.json"