CVE-2026-107161
Fixed in a distro release EPSS <1%CVSS 7.5
A heap-based buffer overflow flaw was found in Cyrus SASL. The add_to_challenge() function in the DIGEST-MD5 plugin computes the size of the buffer needed for a challenge/response field before DIGEST-MD5 quoting is applied, but does not recompute that size when quoting (escaping special characters) makes the value longer. The under-sized buffer is then passed to strcat(), causing a heap-based out-of-bounds write whose size depends on attacker-controlled input. A malicious or on-path DIGEST-MD5 (or HTTP Digest) server can trigger this flaw in a connecting client by supplying a crafted challenge field, such as realm or nonce, most likely resulting in a crash of the client application.
Products: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat Hardened Images, Red Hat OpenShift Container Platform 4
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Debian 12 | cyrus-sasl2 | no fix |
| Debian 13 | cyrus-sasl2 | no fix |
| Debian 14 | cyrus-sasl2 | 2.1.28+dfsg1-12 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | cyrus-sasl | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | cyrus-sasl-bdb | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | cyrus-sasl-saslauthd | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | cyrus-sasl-saslauthd-bdb | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | cyrus-sasl | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | cyrus-sasl-bdb | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | cyrus-sasl-saslauthd | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | cyrus-sasl-saslauthd-bdb | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | cyrus-sasl | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | cyrus-sasl-bdb | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | cyrus-sasl-saslauthd | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | cyrus-sasl | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | cyrus-sasl-bdb | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | cyrus-sasl-saslauthd | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Micro 5.3 | cyrus-sasl | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Micro 5.4 | cyrus-sasl | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Micro 5.5 | cyrus-sasl | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | cyrus-sasl | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | cyrus-sasl-saslauthd | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Module for Legacy 15 SP7 | cyrus-sasl-bdb | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Module for Legacy 15 SP7 | cyrus-sasl-saslauthd-bdb | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | cyrus-sasl-bdb | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | cyrus-sasl-saslauthd | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Server 12 SP5-LTSS | cyrus-sasl | 2.1.26-14.10.1 |
| SUSE Linux Enterprise Server 12 SP5-LTSS | cyrus-sasl-saslauthd | 2.1.26-14.10.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | cyrus-sasl | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | cyrus-sasl-bdb | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | cyrus-sasl-saslauthd | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | cyrus-sasl-saslauthd-bdb | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | cyrus-sasl | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | cyrus-sasl-bdb | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | cyrus-sasl-saslauthd | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | cyrus-sasl-saslauthd-bdb | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | cyrus-sasl | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | cyrus-sasl-bdb | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | cyrus-sasl-saslauthd | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | cyrus-sasl-saslauthd-bdb | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Server 16.0 | cyrus-sasl | 2.1.28-160000.4.1 |
| SUSE Linux Enterprise Server 16.0 | cyrus-sasl-saslauthd | 2.1.28-160000.4.1 |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | cyrus-sasl | 2.1.26-14.10.1 |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | cyrus-sasl-saslauthd | 2.1.26-14.10.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | cyrus-sasl | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | cyrus-sasl-bdb | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | cyrus-sasl-saslauthd | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | cyrus-sasl-saslauthd-bdb | 2.1.27-150300.4.9.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | cyrus-sasl | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | cyrus-sasl-bdb | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | cyrus-sasl-saslauthd | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | cyrus-sasl-saslauthd-bdb | 2.1.28-150500.3.12.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | cyrus-sasl | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | cyrus-sasl-bdb | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | cyrus-sasl-saslauthd | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | cyrus-sasl-saslauthd-bdb | 2.1.28-150600.7.17.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | cyrus-sasl | 2.1.28-160000.4.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | cyrus-sasl-saslauthd | 2.1.28-160000.4.1 |
| Ubuntu 18.04 LTS | cyrus-sasl2 | no fix |
| Ubuntu 20.04 LTS | cyrus-sasl2 | no fix |
| Ubuntu 22.04 LTS | cyrus-sasl2 | no fix |
| Ubuntu 24.04 LTS | cyrus-sasl2 | no fix |
| Ubuntu 26.04 LTS | cyrus-sasl2 | no fix |
| Ubuntu 26.10 | cyrus-sasl2 | no fix |
| Ubuntu Pro 14.04 LTS | cyrus-sasl2 | no fix |
| Ubuntu Pro 16.04 LTS | cyrus-sasl2 | no fix |
| openSUSE Leap 16.0 | cyrus-sasl | 2.1.28-160000.4.1 |
| openSUSE Leap 16.0 | cyrus-sasl-bdb | 2.1.28-160000.4.1 |
| openSUSE Leap 16.0 | cyrus-sasl-saslauthd | 2.1.28-160000.4.1 |
| openSUSE Leap 16.0 | cyrus-sasl-saslauthd-bdb | 2.1.28-160000.4.1 |
| openSUSE Tumbleweed | cyrus-sasl | 2.1.28-13.1 |