codeplea tinyexpr new_expr buffer size

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.1$0-$5k0.00+

Summaryinfo

A vulnerability labeled as critical has been found in codeplea tinyexpr. This impacts the function new_expr. The manipulation results in buffer size. This vulnerability is known as CVE-2026-88355. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability, which was classified as critical, was found in codeplea tinyexpr (the affected version unknown). Affected is the function new_expr. The manipulation with an unknown input leads to a buffer size vulnerability. CWE is classifying the issue as CWE-131. The product does not correctly calculate the size to be used when allocating a buffer, which could lead to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-88355 since 09/10/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/24/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

Name

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.1

VulDB Base Score: 6.3
VulDB Temp Score: 6.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer size
CWE: CWE-131 / CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/10/2026 CVE reserved
09/24/2026 +14 days Advisory disclosed
09/24/2026 +0 days VulDB entry created
09/24/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Not defined

CVE: CVE-2026-88355 (🔒)
GCVE (CVE): GCVE-0-2026-88355
GCVE (VulDB): GCVE-100-409440

Entryinfo

Created: 09/24/2026 17:56
Changes: 09/24/2026 17:56 (52)
Complete: 🔍
Cache ID: 216::103

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