Red Hat Enterprise Linux up to 10 RainerScript replace heap-based overflow

Summaryinfo

A vulnerability marked as critical has been reported in Red Hat Enterprise Linux 6/7/8/9/10. This vulnerability affects the function replace of the component RainerScript. Performing a manipulation results in heap-based overflow. This vulnerability is reported as CVE-2026-78002. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Red Hat Enterprise Linux 6/7/8/9/10. It has been classified as critical. This affects the function replace of the component RainerScript. The manipulation with an unknown input leads to a heap-based overflow vulnerability. CWE is classifying the issue as CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). This is going to have an impact on integrity, and availability. The summary by CVE is:

A flaw was found in rsyslog. An unauthenticated remote attacker can trigger a heap buffer overflow in the RainerScript `replace()` function by sending specially crafted syslog messages. This vulnerability arises from an incorrect buffer size calculation during string replacement, causing memory corruption. Successful exploitation can lead to a denial of service (DoS) for the affected system.

It is possible to read the advisory at access.redhat.com. This vulnerability is uniquely identified as CVE-2026-78002 since 08/21/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/27/2026).

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

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Red Hat

Name

• Enterprise Linux

Version

• 6
• 7
• 8
• 9
• 10

License

• commercial

Website

• Vendor: https://www.redhat.com/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion