🛡️ CVE-2023-3635 — okio

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is high, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity none, availability high.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

• Attack vector: Network — reachable from anywhere that can route to the service.
• Attack complexity: High — the attacker first has to win a race, learn a secret or otherwise prepare the target.
• Privileges required: None — an unauthenticated stranger can try it.
• User interaction: None — nobody has to be tricked into anything.
• Scope: Unchanged — the damage stays inside the vulnerable component.
• Confidentiality impact: None.
• Integrity impact: None.
• Availability impact: High — total loss, or loss the attacker controls.

Weakness class

CVE-2023-3635 is classified as CWE-195: Signed to Unsigned Conversion Error. The product uses a signed primitive and performs a cast to an unsigned primitive, which can produce an unexpected value if the value of the signed primitive can not be represented using an unsigned primitive.

Affected software

CVE-2023-3635 is recorded against 3 packages.

• com.squareup.okio:okio (fixed in 1.17.6)
• com.squareup.okio:okio-jvm (from 2.0.0-RC1 up to 3.4.0)
• okio (from 2.0.0 up to 3.4.0)

Timeline and source

Published on 12 July 2023 and last revised on 4 February 2026. No public exploit is currently recorded for this entry. A vendor advisory or fix has been published. Record sourced from NVD.

References

nvd.nist.gov (Advisory)
github.com (Web)
github.com (Web)
github.com (Web)
github.com (Web)
github.com (Package)
github.com (Web)
research.jfrog.com (Web)

Other advisories for this package

com.squareup.okio:okio has other advisories on record. If you are patching this one, these are worth checking on the same host:

• CLSA-2025-1763597219 (published 4 Aug 2026)
• CLSA-2025-1750809965 (published 4 Aug 2026)

Same weakness in other software

These advisories are the same class of weakness (CWE-195: Signed to Unsigned Conversion Error) in other software:

• CVE-2026-55737 (7.5 High, published 27 Jul 2026)
• CVE-2026-55991 (5.9 Medium, published 22 Jul 2026)
• CVE-2026-26981 (6.5 Medium, published 13 Jul 2026)
• CVE-2026-41682 (published 8 May 2026)
• CVE-2025-67897 (5.3 Medium, published 14 Dec 2025)
• CVE-2025-65495 (7.5 High, published 24 Nov 2025)
• CVE-2025-30646 (6.5 Medium, published 9 Apr 2025)
• CVE-2025-24792 (4.4 Medium, published 29 Jan 2025)

CVE-2023-3635 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Affected Packages

References