CVE-2026-59099: Apereo CAS 7.3.0 before 8.0.0-RC6 contains a cryptographic vulnerability that allows remote unauthenticated attackers to recover plaintext conversation state by exploiting AES-GCM
Apereo CAS 7.3.0 before 8.0.0-RC6 contains a cryptographic vulnerability that allows remote unauthenticated attackers to recover plaintext conversation state by exploiting AES-GCM initialization vector reuse across the server lifetime. Attackers can collect multiple client-side webflow execution tokens from the unauthenticated login page and perform known-plaintext analysis to decrypt the webflow conversation state due to keystream reuse caused by a fixed all-zero IV paired with the same encryption key.
Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-59099
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-590990.36% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 28% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-59099 | coverage & exploitation status | NVD · CVE.org |
More from NVD Recent CVEs
- highCVE-2026-58281: Deserialization of untrusted data in Microsoft Edge (Chromium-based) allows an unauthorized at…2026-07-11
- mediumCVE-2026-10660: The Bluetooth BAP Broadcast Assistant GATT client in subsys/bluetooth/audio/bap_broadcast_assi…2026-07-11
- lowCVE-2026-61870: ImageMagick before 7.1.2-26 contains a memory leak vulnerability in the VIFF encoder when memo…2026-07-11
- lowCVE-2026-61861: ImageMagick before 7.1.2-26 contains a use-after-free vulnerability in the FormatMagickCaption…2026-07-11
- lowCVE-2026-61858: ImageMagick before 7.1.2-26 contains a policy bypass vulnerability in the APNG encoder and ext…2026-07-11