PT-2021-17353 · Tencent · Tencent Wechat

Wen Guang Jiao · Published 2021-02-24 · Updated 2021-04-22 · CVE-2021-27247

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Name of the Vulnerable Software and Affected Versions: Tencent WeChat version 2.9.5

Description: This issue allows remote attackers to disclose sensitive information on affected installations. User interaction is required, where the target must visit a malicious page or open a malicious file. The flaw exists within the WXAM decoder due to the lack of proper validation of user-supplied data, resulting in a read past the end of an allocated buffer. An attacker can leverage this, in conjunction with other issues, to execute arbitrary code in the context of the current process.

Recommendations: For version 2.9.5, as a temporary workaround, consider disabling the WXAM decoder function until a patch is available. Restrict access to potentially malicious pages or files to minimize the risk of exploitation. At the moment, there is no information about a newer version that contains a fix for this issue.

Fix

Out of bounds Read

Weakness Enumeration

CWE-125

Related Identifiers

CVE-2021-27247

ZDI-21-217

Affected Products

Tencent Wechat

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2021-27247 · Security Note
• https://osv.dev/vulnerability/CVE-2021-27247 · Vendor Advisory
• https://zerodayinitiative.com/advisories/ZDI-21-217 · Security Note
• https://t.me/cvenotify/13534 · Telegram Post