Alpine: multiple rsyslog packages: security update to 8.2608.0-r0

high Tenable Self-Hosted Container Security Plugin ID 478598

Description

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

- A unauthenticated remote peer may lead rsyslogd to crash due to a flaw in the optional imptcp module. A
crafted input sequence during oversize-frame recovery can cause an invalid internal message length and
terminate rsyslogd. No confidentiality or integrity impact, privilege escalation, or code execution has
been identified. imtcp and the default imptcp framing modes are not affected. (CVE-2026-19654)

- Rsyslog is a rocket-fast system for log processing. From 8.2110.0 until 8.2604.0, the optional imhttp
module's parse_auth_header function in contrib/imhttp/imhttp.c allocates a zero-byte heap buffer with
calloc(0, len) when an HTTP Basic Authorization value exceeds its fixed work buffer, then passes that
pointer to apr_base64_decode. An unauthenticated remote attacker can send an oversized encoded credential
to an imhttp endpoint configured for Basic Authentication, causing decoded data to overwrite adjacent heap
memory before credential validation. Deployments that do not install, load, and use imhttp with Basic
Authentication are not affected. The demonstrated impact is a process crash that interrupts log
collection, and code execution has not been demonstrated. This issue is fixed in version 8.2604.0.
(CVE-2026-55556)

- Rsyslog is a rocket-fast system for log processing. From 7.5.4 until 8.2606.0, the optional mmpstrucdata
plugin's parseSD_PARAM function in plugins/mmpstrucdata/mmpstrucdata.c stores RFC5424 parameter values in
a fixed pVal[32 * 1024] stack buffer and calls parsePARAM_VALUE without supplying the destination size. A
remote unauthenticated attacker whose crafted RFC5424 message reaches an action using mmpstrucdata can
provide a structured-data parameter larger than that buffer when MaxMessageSize permits it, causing an
attacker-controlled stack overwrite. Deployments that do not install and use the plugin, or whose
effective message-size limit remains below the required threshold, are not affected by this issue. The
demonstrated impact is a crash and interruption of log collection; code execution is not demonstrated.
This issue is fixed in version 8.2606.0. (CVE-2026-61548)

- 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. (CVE-2026-78002)

Solution

Update the rsyslog library and its related packages to version 8.2608.0-r0 or later.

See Also

https://security.alpinelinux.org/vuln/CVE-2026-19654

https://security.alpinelinux.org/vuln/CVE-2026-55556

https://security.alpinelinux.org/vuln/CVE-2026-61548

https://security.alpinelinux.org/vuln/CVE-2026-78002

https://security.alpinelinux.org/vuln/CVE-2026-93403

Plugin Details

Severity: High

ID: 478598

Version: Revision 1.1

Type: Local

Published: 11/6/2026

Updated: 11/6/2026

Supported Sensors: Agentless Assessment

Risk Information

VPR

Risk Factor: Medium

Score: 5

Percentile: 93.13

CVSS v2

Risk Factor: High

Base Score: 7.6

Temporal Score: 5.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-61548

CVSS v3

Risk Factor: High

Base Score: 8.1

Temporal Score: 7.1

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

CVSS v4

Risk Factor: High

Base Score: 8.2

Threat Score: 4.6

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS Score Source: CVE-2026-55556

Vulnerability Information

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 7/6/2026

Reference Information

CVE: CVE-2026-19654, CVE-2026-55556, CVE-2026-61548, CVE-2026-78002, CVE-2026-93403

IAVA: 2026-A-0775-S, 2026-A-0983