Out-of-bounds Read in Stefanberger Swtpm
CVE-2022-23645
swtpm is a libtpms-based TPM emulator with socket, character device, and Linux CUSE interface. Versions prior to 0.5.3, 0.6.2, and 0.7.1 are vulnerable to out-of-bounds read. A specially crafted header of swtpm's state, where the blobheader's hdrsize indicator has an invalid value, may cause an out-of-bounds access when the byte array representing the state of the TPM is accessed. This will likely crash swtpm or prevent it from starting since the state cannot be understood. Users should upgrade to swtpm v0.5.3, v0.6.2, or v0.7.1 to receive a patch. There are currently no known workarounds.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (32.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 32.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Stefanberger Swtpm — versions < 0.5.3, >= 0.6.0, < 0.6.2, = 0.7.0
- Swtpm Project — versions 0.7.0
- Fedoraproject Fedora — versions 35
- Red Hat Enterprise Linux — versions 8.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/stefanberger/swtpm/security/advisories/GHSA-2qgm-8xf4-3hqw (Patch, Third Party Advisory)
- github.com/stefanberger/swtpm/commit/9f740868fc36761de27df3935513bdebf8852d19 (Patch, Third Party Advisory)
- github.com/stefanberger/swtpm/releases/tag/v0.5.3 (Third Party Advisory, Release Notes)
- github.com/stefanberger/swtpm/releases/tag/v0.6.2 (Third Party Advisory, Release Notes)
- github.com/stefanberger/swtpm/releases/tag/v0.7.1 (Third Party Advisory, Release Notes)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
Frequently asked questions
- What is CVE-2022-23645?
- CVE-2022-23645 is a medium-severity vulnerability in Stefanberger Swtpm, classified under Out-of-bounds Read. CVSS score: 6.2/10. Published 2022-02-18.
- How severe is CVE-2022-23645?
- Medium severity. CVSS v3 base score is 6.2 out of 10.
- Is CVE-2022-23645 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.