ALPINE-CVE-2021-31535
Record from OSV · Published May 27, 2021
LookupCol.c in X.Org X through X11R7.7 and libX11 before 1.7.1 might allow remote attackers to execute arbitrary code. The libX11 XLookupColor request (intended for server-side color lookup) contains a flaw allowing a client to send color-name requests with a name longer than the maximum size allowed by the protocol (and also longer than the maximum packet size for normal-sized packets). The user-controlled data exceeding the maximum size is then interpreted by the server as additional X protocol requests and executed, e.g., to disable X server authorization completely. For example, if the victim encounters malicious terminal control sequences for color codes, then the attacker may be able to take full control of the running graphical session.
Fixed versions
Upgrade to a fixed version or later. Language registries are listed first, then Linux distributions, then vendor products.
| Package | Ecosystem | Fixed in |
|---|---|---|
| libx11 | Alpine:v3.13 | 1.7.1-r0 |
| libx11 | Alpine:v3.16 | 1.7.1-r0 |
| libx11 | Alpine:v3.22 | 1.7.1-r0 |
| libx11 | Alpine:v3.14 | 1.7.1-r0 |
| libx11 | Alpine:v3.11 | 1.6.12-r1 |
| libx11 | Alpine:v3.10 | 1.6.12-r1 |
| libx11 | Alpine:v3.24 | 1.7.1-r0 |
| libx11 | Alpine:v3.18 | 1.7.1-r0 |
| libx11 | Alpine:v3.17 | 1.7.1-r0 |
| libx11 | Alpine:v3.19 | 1.7.1-r0 |
| libx11 | Alpine:v3.23 | 1.7.1-r0 |
| libx11 | Alpine:v3.12 | 1.6.12-r1 |
3 more packages have a fixed version. See every fix in Lookup.
Risk scores
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Alpine:v3.13 | libx11 | 0, 1.2.2-r0, 1.5.0-r0 |
| Alpine:v3.16 | libx11 | 0, 1.3.6-r0, 1.6.8-r0 |
| Alpine:v3.22 | libx11 | 1.1.99.2-r0, 1.4.99.901-r0, 1.3.4-r0 |
| Alpine:v3.14 | libx11 | 0, 1.6.9-r0, 1.4.4-r0 |
| Alpine:v3.11 | libx11 | 0, 1.1.99.2-r1, 1.2-r0 |
| Alpine:v3.10 | libx11 | 0, 1.3-r0, 1.5.0-r0 |
| Alpine:v3.24 | libx11 | 0 |
| Alpine:v3.18 | libx11 | 0, 1.2-r0, 1.2.2-r0 |
| Alpine:v3.17 | libx11 | 1.3.3-r0, 1.1.99.2-r0, 1.6.7-r0 |
| Alpine:v3.19 | libx11 | 0, 1.1.99.2-r0, 1.2.1-r0 |
| Alpine:v3.23 | libx11 | 1.6.8-r1, 1.4.3-r2, 1.3.3-r0 |
| Alpine:v3.12 | libx11 | 1.2.2-r0, 1.3-r0, 1.3.2-r0 |
| Alpine:v3.21 | libx11 | 0, 1.1.99.2-r0, 1.6.0-r0 |
| Alpine:v3.20 | libx11 | 0, 1.1.99.2-r1, 1.2-r0 |
| Alpine:v3.15 | libx11 | 1.6.12-r0, 1.6.7-r0, 1.7.0-r0 |
Timeline
- May 27, 2021 CVE Published
- Jun 15, 2026 CVE Updated
- Aug 8, 2026 Distribution Patch
Query this with the API
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