Metrics
Affected Vendors & Products
Mon, 28 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Expat through 2.8.4 fails to validate low surrogates following high surrogates in UTF-16 input, allowing malformed UTF-16 sequences to be accepted. Attackers can craft UTF-16 encoded XML with lone high surrogates that consume following code units, hiding markup characters from the parser and enabling XML injection attacks. | Expat before 2.8.5 fails to validate that a high surrogate in UTF-16 input is followed by a low surrogate, allowing malformed UTF-16 sequences to be accepted. Attackers can supply UTF-16 encoded XML containing lone high surrogates that consume the following code unit, causing Expat to pass unpaired surrogates to applications built with XML_UNICODE and to silently replace input characters in other builds. |
| Title | Expat through 2.8.4 Malformed UTF-16 Acceptance via Unchecked Surrogate | Expat before 2.8.5 Malformed UTF-16 Acceptance via Unchecked Surrogate |
| References |
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Wed, 23 Sep 2026 00:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-91 | |
| References |
| |
| Metrics |
threat_severity
|
threat_severity
|
Mon, 21 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Sun, 20 Sep 2026 11:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Libexpat
Libexpat expat |
|
| Vendors & Products |
Libexpat
Libexpat expat |
Sat, 19 Sep 2026 23:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Expat through 2.8.4 fails to validate low surrogates following high surrogates in UTF-16 input, allowing malformed UTF-16 sequences to be accepted. Attackers can craft UTF-16 encoded XML with lone high surrogates that consume following code units, hiding markup characters from the parser and enabling XML injection attacks. | |
| Title | Expat through 2.8.4 Malformed UTF-16 Acceptance via Unchecked Surrogate | |
| First Time appeared |
Libexpat Project
Libexpat Project libexpat |
|
| Weaknesses | CWE-176 | |
| CPEs | cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Libexpat Project
Libexpat Project libexpat |
|
| References |
| |
| Metrics |
cvssV3_1
|
Status: PUBLISHED
Assigner: VulnCheck
Published: 2026-09-19T22:58:11.224Z
Updated: 2026-09-28T16:11:06.770Z
Reserved: 2026-09-19T10:55:49.093Z
Link: CVE-2026-93990
Updated: 2026-09-21T15:11:05.367Z
Status : Awaiting Analysis
Published: 2026-09-19T23:17:10.203
Modified: 2026-09-28T17:17:53.037
Link: CVE-2026-93990