0.0
NA
CVE-2026-88355
tinyexpr Buffer Overflow Vulnerability
Description

An incorrect buffer size calculation vulnerability exists in tinyexpr commit 4a7456e in new_expr(). For arity-0 expression nodes, including constants, variables, and zero-argument functions, the function allocates less memory than sizeof(te_expr) but treats the returned allocation as a complete te_expr object. This results in undefined behavior and can cause deterministic process termination in UBSan-instrumented builds.

INFO

Published Date :

Sept. 24, 2026, 4:17 p.m.

Last Modified :

Sept. 24, 2026, 4:17 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-88355 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Fix buffer size calculation in new_expr to correctly allocate memory for expression nodes.
  • Review and correct buffer size calculation in new_expr function.
  • Ensure allocation size matches expected te_expr object size.
  • Test thoroughly for memory corruption and crashes.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-88355.

URL Resource
https://github.com/codeplea/tinyexpr/issues/145
https://github.com/szaydel/tinyexpr/commit/fe7459728c2ab8d2f91365abe56601cdd0e24f9b
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-88355 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-88355 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-88355 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-88355 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 24, 2026

    Action Type Old Value New Value
    Added Description An incorrect buffer size calculation vulnerability exists in tinyexpr commit 4a7456e in new_expr(). For arity-0 expression nodes, including constants, variables, and zero-argument functions, the function allocates less memory than sizeof(te_expr) but treats the returned allocation as a complete te_expr object. This results in undefined behavior and can cause deterministic process termination in UBSan-instrumented builds.
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/88xxx/CVE-2026-88355.json">CVE-2026-88355</a>
    Added Reference https://github.com/codeplea/tinyexpr/issues/145
    Added Reference https://github.com/szaydel/tinyexpr/commit/fe7459728c2ab8d2f91365abe56601cdd0e24f9b
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.