9.1

CVE-2026-75803: openssl

CVSS: 9.1v3.1CriticalAnalyzed
AliasesALPINE-CVE-2026-75803RHSA-2026:59260RHSA-2026:62786
Published 25-08-2026Last modified 01-09-2026
Open JSON

Vulnerability summary

CVE-2026-75803 is a critical (CVSS 9.1) vulnerability in openssl. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.1% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.23%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 19 · Related 12
MGASA-2026-0353OPENSUSE-SU-2026:11623-1OPENSUSE-SU-2026:21744-1RHSA-2026:42825RHSA-2026:55543RHSA-2026:59635

Timeline

  1. 25-08-2026
    PublishedVulnerability first disclosed.
  2. 01-09-2026
    Last modifiedVulnerability information updated.

Description

Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ciphertext can report success without verifying the supplied authentication tag when the operation is finalized by calling the EVP_Cipher() function. Impact summary: Applications calling EVP_Cipher() on an empty ciphertext and expecting the call to check the AEAD tag may accept forged messages. CWE: CWE-354 (Improper Validation of Integrity Check Value) Description: The EVP_Cipher() API call for AEAD ciphers behaves like a one shot encryption and decryption call. It also verifies the AEAD tag after the decryption operation. However for AES-OCB and ChaCha20-Poly1305 ciphers it skipped the AEAD tag verification when an empty ciphertext was passed to the function. The callers of this function might believe that a successful return indicates a valid AEAD tag for these ciphers, even when that has not truly been validated in this case. FIPS impact: no The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this CVE as the affected algorithms are not FIPS approved and thus not implemented in the FIPS module.

CVSS metrics

7 scores · 7 sources · 1 version

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

13%

Versus all other CVEs

30-day change

+0.01 pp

From 0.22% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.23%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Redhat8 products
  • bootupd< 0:0.2.36-3.hum1
  • ruby3.4< 0:3.4.10-31.7.hum1
  • ruby3.4-bundled-gems< 0:3.4.10-31.7.hum1
  • ruby3.4-default-gems< 0:3.4.10-31.7.hum1
  • ruby3.4-devel< 0:3.4.10-31.7.hum1
Chainguard7 products
  • eco-python-openssl-4< 4.0.2-r0
  • eco-python-openssl-4-pyca< 4.0.2-r0
  • eco-python-openssl-4-pyca-dev< 4.0.2-r0
  • openssl-provider-fips-3.4.0All versions (No fix recorded)
  • openssl-provider-fips-3.4.0-dbgAll versions (No fix recorded)
Ubuntu5 products
  • edk2< 2024.02-2ubuntu0.10 | All versions (No fix recorded) | < 2025.11-3ubuntu7.3
  • edk2-hweAll versions (No fix recorded)
  • nodejsAll versions (No fix recorded)
  • openssl< 3.0.2-0ubuntu1.29 | All versions (No fix recorded) | < 3.0.2-0ubuntu1.29+Fips1 | < 3.0.13-0ubuntu3.15 | < 3.5.5-1ubuntu3.5
  • openssl-fipsAll versions (No fix recorded) | < 3.0.13-0ubuntu3.15+Fips1
Alpine1 product
  • openssl≥ 3.0.0, < 3.3.7-r1 | ≥ 3.0.0, < 3.5.8-r0
Debian1 product
  • openssl< 3.0.22-1~deb12u1 | < 3.5.7-1~deb13u2 | < 3.6.4-1
Openssl1 product
  • openssl≥ 3.0.0, < 3.0.22 | ≥ 3.4.0, < 3.4.7 | ≥ 3.5.0, < 3.5.8 | ≥ 3.6.0, < 3.6.4 | ≥ 4.0.0, < 4.0.2

6 vendors · 23 products

References

23 links
Show all 23 references