VDB-436609 · CVE-2026-123338 · GCVE-0-2026-123338

Apache DataSketches REQ sketch out-of-bounds write

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.3	$5k-$25k	0.00+

Summaryinfo

A vulnerability was found in Apache DataSketches. It has been classified as critical. This affects an unknown function of the component REQ sketch. This manipulation causes out-of-bounds write. The identification of this vulnerability is CVE-2026-123338. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as critical was found in Apache DataSketches (unknown version). Affected by this vulnerability is an unknown code block of the component REQ sketch. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability.

This vulnerability is known as CVE-2026-123338. The exploitation appears to be easy. The attack can be launched remotely. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 11/13/2026).

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

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Apache

Name

DataSketches

License

open-source

Website

Vendor: https://www.apache.org/

CPE 2.3info

🔒

CPE 2.2info

🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

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

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

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

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

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/13/2026 Advisory disclosed
11/13/2026 +0 days VulDB entry created
11/13/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apache.org

Status: Not defined

CVE: CVE-2026-123338 (🔒)

GCVE (CVE): GCVE-0-2026-123338
GCVE (VulDB): GCVE-100-436609

Entryinfo

Created: 11/13/2026 04:34
Changes: 11/13/2026 04:34 (47)
Complete: 🔍
Cache ID: 216::103