CVE-2026-80255
published 2026-09-06CVE-2026-80255: A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the `Secure` attribute causes curl to store…
PriorityP343high7.5CVSS 3.1
AVNACLPRNUINSUCHINAN
EPSS
0.48%
39.1th percentile
A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of
space (ascii code 32) immediately before the `Secure` attribute causes curl to
store the cookie without its Secure flag. The cookie might then wrongfully be
sent over plaintext HTTP on subsequent requests to the same host.
Affected
18 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| curl | curl | — | — |
| curl | curl | — | — |
| curl | curl | — | — |
| curl | curl | — | — |
| curl | curl | — | — |
| curl | curl | — | — |
| curl | curl | — | — |
| curl | curl | — | — |
| curl | curl | — | — |
| curl | curl | — | — |
| curl | curl | >= 1aea05a6c2699e80c75936d58569851555acd603 < 4f6aa41a0145e930e766775dbe860883d350aa0a | 4f6aa41a0145e930e766775dbe860883d350aa0a |
| curl | curl | >= 8.13.0 < 8.14.2 | 8.14.2 |
| curl | curl | >= 8.15.0 < 8.16.1 | 8.16.1 |
| curl | curl | >= 8.17.0 < 8.20.1 | 8.20.1 |
| curl | curl | >= 8.21.0 < 8.22.0 | 8.22.0 |
| haxx | curl | — | — |
| haxx | curl | >= 8.13.0 < 8.22.0 | 8.22.0 |
| ubuntu | curl | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
vendor_redhat7.5HIGH
vendor_ubuntu7.4HIGH
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Ubuntu
curl vulnerabilities
vendor_ubuntu·2026-09-24·CVSS 7.4
CVE-2026-80229 [HIGH] curl vulnerabilities
Title: curl vulnerabilities
Summary: Several security issues were fixed in curl.
Eunsoo Kim discovered that curl incorrectly handled SASL negotiation for
LDAP authentication in certain circumstances. A machine-in-the-middle
attacker could possibly use this issue to bypass peer validation. This
issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS.
(CVE-2026-13608)
Stephan Zeisberg discovered that curl incorrectly handled HTTP/2 Server
Push streams when sharing connections between handles. A remote attacker
could possibly use this issue to cause curl to crash, resulting in a denial
of service, or execute arbitrary code. (CVE-2026-18924)
Stanislav Fort discovered that curl incorrectly managed the lifetime of
pooled TLS connections when using the multi interface. An attacker could
pos
Red Hat
curl: curl: Information disclosure due to secure cookie attribute bypass
vendor_redhat·2026-09-06·CVSS 7.5
CVE-2026-80255 [HIGH] CWE-201 curl: curl: Information disclosure due to secure cookie attribute bypass
curl: curl: Information disclosure due to secure cookie attribute bypass
A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of
space (ascii code 32) immediately before the `Secure` attribute causes curl to
store the cookie without its Secure flag. The cookie might then wrongfully be
sent over plaintext HTTP on subsequent requests to the same host.
A flaw was found in curl. When a `Set-Cookie:` header uses a tab character instead of a space before the `Secure` attribute, curl incorrectly stores the cookie without the Secure flag. This can lead to information disclosure, as the cookie may then be sent over unencrypted HTTP connections to the same host, potentially exposing sensitive data.
Statement: This Low impact information disclosure flaw in curl occurs when a `Se
GHSA
A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the `Secure` attribute causes curl to store the cookie without its Secure flag.
ghsa_unreviewed·2026-09-06
CVE-2026-80255 A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the `Secure` attribute causes curl to store the cookie without its Secure flag.
A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of
space (ascii code 32) immediately before the `Secure` attribute causes curl to
store the cookie without its Secure flag. The cookie might then wrongfully be
sent over plaintext HTTP on subsequent requests to the same host.
VulDB
curl up to 8.21.0 Cookie insertion of sensitive information into sent data (EUVD-2026-72151)
vuldb·2026-09-06
CVE-2026-80255 [LOW] curl up to 8.21.0 Cookie insertion of sensitive information into sent data (EUVD-2026-72151)
A vulnerability labeled as problematic has been found in curl up to 8.21.0. The impacted element is an unknown function of the component Cookie Handler. Executing a manipulation can lead to insertion of sensitive information into sent data.
This vulnerability is tracked as CVE-2026-80255. The attack can be launched remotely. No exploit exists.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-80255 curl: curl: Information disclosure due to secure cookie attribute bypass [fedora-all]
bugzilla·2026-09-22·CVSS 7.5
CVE-2026-80255 [HIGH] CVE-2026-80255 curl: curl: Information disclosure due to secure cookie attribute bypass [fedora-all]
CVE-2026-80255 curl: curl: Information disclosure due to secure cookie attribute bypass [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of
space (ascii code 32) immediately before the `Secure` attribute causes curl to
store the cookie without its Secure flag. The cookie might then wrongfully be
sent over plaintext HTTP on subsequent requests to the same host.
Bugzilla
CVE-2026-80255 mingw-curl: curl: Information disclosure due to secure cookie attribute bypass [fedora-all]
bugzilla·2026-09-22·CVSS 7.5
CVE-2026-80255 [HIGH] CVE-2026-80255 mingw-curl: curl: Information disclosure due to secure cookie attribute bypass [fedora-all]
CVE-2026-80255 mingw-curl: curl: Information disclosure due to secure cookie attribute bypass [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of
space (ascii code 32) immediately before the `Secure` attribute causes curl to
store the cookie without its Secure flag. The cookie might then wrongfully be
sent over plaintext HTTP on subsequent requests to the same host.
Bugzilla
CVE-2026-80255 curl: curl: Information disclosure due to secure cookie attribute bypass
bugzilla·2026-09-06·CVSS 7.5
CVE-2026-80255 [HIGH] CVE-2026-80255 curl: curl: Information disclosure due to secure cookie attribute bypass
CVE-2026-80255 curl: curl: Information disclosure due to secure cookie attribute bypass
A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of
space (ascii code 32) immediately before the `Secure` attribute causes curl to
store the cookie without its Secure flag. The cookie might then wrongfully be
sent over plaintext HTTP on subsequent requests to the same host.
2026-09-06
Published