CVE-2023-51651 | Potential URI resolution path traversal in the AWS SDK for PHP

AWS SDK for PHP is the Amazon Web Services software development kit for PHP. Within the scope of requests to S3 object keys and/or prefixes containing a Unix double-dot, a URI path traversal is possible. The issue exists in the `buildEndpoint` method in the RestSerializer component of the AWS SDK for PHP v3 prior to 3.288.1. The `buildEndpoint` method relies on the Guzzle Psr7 UriResolver utility, which strips dot segments from the request path in accordance with RFC 3986. Under certain conditions, this could lead to an arbitrary object being accessed. This issue has been patched in version 3.288.1.

Published: 2023-12-22 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-51651 is rated Low Risk (34.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.38%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-51651

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.10% 0.38% +0.28%
2 2025-11-21 0.25% 0.10% -0.15%
3 2025-11-18 0.25%

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-51651

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.0 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
0.8 5.2 [email protected]
3.3 3.1 LOW
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
1.8 1.4 [email protected]

Weakness enumeration for CVE-2023-51651

GitHub Security Advisory for CVE-2023-51651

GHSA-557v-xcg6-rm5m · Severity: medium · Ecosystem: composer — Potential URI resolution path traversal in the AWS SDK for PHP

OS Trackers for CVE-2023-51651

vendor priority summary link
ubuntu medium CVE-2023-51651 medium priority: Ubuntu including 1 source packages (aws-sdk-for-php), 8 status rows across 8 suites (focal, jammy, noble, oracular, plucky, questing, upstream, xenial): DNE 6, needs-triage 2. https://ubuntu.com/security/CVE-2023-51651

Affected software / configurations for CVE-2023-51651

Vendor Product Version Raw CPE
amazon aws_software_development_kit < 3.288.1 cpe:2.3:a:amazon:aws_software_development_kit:*:*:*:*:*:php:*:*

References for CVE-2023-51651

cvelogic Threat Intelligence