CVE-2025-9086: Out of bounds read for cookie path
Vulnerability summary
CVE-2025-9086 is a high (CVSS 7.5) Out-of-bounds Read vulnerability in curl. EPSS estimates a 1.46% chance of exploitation in the next 30 days, higher than 73.6% of scored vulnerabilities. 1 public exploit is recorded.
Public exploit (reference, Date unknown)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 14 · Related 11Timeline
- 12-09-2025PublishedVulnerability first disclosed.
- 15-09-2026Last modifiedVulnerability information updated.
Description
1. A cookie is set using the `secure` keyword for `https://target` 2. curl is redirected to or otherwise made to speak with `http://target` (same hostname, but using clear text HTTP) using the same cookie set 3. The same cookie name is set - but with only a slash as path (`path="/"`). Since this site is not secure, the cookie *should* be ignored. 4. A bug in the path comparison logic makes curl read outside a heap buffer boundary The bug either causes a crash or it potentially makes the comparison come to the wrong conclusion and lets the clear-text site override the contents of the secure cookie, contrary to expectations and depending on the memory contents immediately following the single-byte allocation that holds the path. The presumed and correct behavior would be to plainly ignore the second set of the cookie since it was already set as secure on a secure host so overriding it on an insecure host should not be okay.
CVSS metrics
6 scores · 6 sources · 1 version- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · Red hatEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LDiffers
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
1.46%
Chance of exploitation in the next 30 days
Percentile
74%
Versus all other CVEs
30-day change
Increase +0.07 pp
From 1.40% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
1 foundExploit Reference (hackerone.com)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Redhat10 products
- curl< 0:7.76.1-31.el9_6.2 | < 0:7.76.1-29.el9_4.3 | < 0:7.76.1-14.el9_0.12 | < 0:7.76.1-23.el9_2.8 | < 0:7.61.1-34.el8_10.9 | < 0:7.76.1-35.el9_7.3 | < 0:8.12.1-1.el10_0.4 | < 0:8.12.1-2.el10_1.2
- curl-debuginfo< 0:7.76.1-31.el9_6.2 | < 0:7.61.1-34.el8_10.9 | < 0:7.76.1-35.el9_7.3 | < 0:8.12.1-2.el10_1.2
- curl-debugsource< 0:7.76.1-31.el9_6.2 | < 0:7.61.1-34.el8_10.9 | < 0:7.76.1-35.el9_7.3 | < 0:8.12.1-2.el10_1.2
- curl-minimal< 0:7.76.1-31.el9_6.2 | < 0:7.76.1-29.el9_4.3 | < 0:7.76.1-14.el9_0.12 | < 0:7.76.1-23.el9_2.8 | < 0:7.76.1-35.el9_7.3
- curl-minimal-debuginfo< 0:7.76.1-31.el9_6.2 | < 0:7.61.1-34.el8_10.9 | < 0:7.76.1-35.el9_7.3
Debian2 products
- curl< 7.74.0-1.3+deb11u16 | < 8.14.1-2+deb13u1 | < 8.16.0~rc2-1
- debian_linuxEOL11.0
Alpine1 product
- curl≥ 8.13.0, < 8.14.1-r2 | ≥ 8.13.0, < 8.16.0-r0
Chainguard1 product
- libcurl4All versions (No fix recorded)
Curl1 product
- curl≥ 8.13.0, < 8.14.2 | ≥ 8.15.0, < 8.16.0 | ≥ 1aea05a6c2699e80c75936d58569851555acd603, < c6ae07c6a541e0e96d0040afb62b45dd37711300 | 8.15.0 | 8.14.1 | 8.14.0 | 8.13.0
Haxx1 product
- curl≥ 8.13.0, < 8.16.0
Mageia1 product
- curl< 7.88.1-4.8.mga9
Ubuntu1 product
- curl< 8.14.1-2ubuntu1.1
Wolfi1 product
- libcurl4All versions (No fix recorded)
9 vendors · 19 products
