- Issued:
- 2026-09-25
- Updated:
- 2026-09-25
RHSA-2026:72183 - Security Advisory
Synopsis
Critical: unbound security update
Type/Severity
Security Advisory: Critical
Red Hat Lightspeed patch analysis
Identify and remediate systems affected by this advisory.
Topic
An update for unbound is now available for Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support and Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On.
Red Hat Product Security has rated this update as having a security impact of Critical. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
Description
The unbound packages provide a validating, recursive, and caching DNS or DNSSEC resolver.
Security Fix(es):
- unbound: Unbound: Heap buffer overflow and possible Remote Code Execution when digesting DNSKEY (CVE-2026-81642)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Solution
For details on how to apply this update, which includes the changes described in this advisory, refer to:
Affected Products
- Red Hat Enterprise Linux for x86_64 - Extended Life Cycle Long Life 8.4 x86_64
- Red Hat Enterprise Linux Server - AUS 8.4 x86_64
- Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle Long Life 8.4 aarch64
- Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle Long Life 8.4 ppc64le
- Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle Long Life 8.4 s390x
Fixes
- BZ - 2535059 - CVE-2026-81642 unbound: Unbound: Heap buffer overflow and possible Remote Code Execution when digesting DNSKEY
CVEs
Red Hat Enterprise Linux for x86_64 - Extended Life Cycle Long Life 8.4
| SRPM | |
|---|---|
| unbound-1.7.3-15.el8_4.4.src.rpm | SHA-256: 414d8fd1b1e6e9d4c6f0349eba1edf0b06d7a2bc5b8cded6e8ddcec78d22d4ba |
| x86_64 | |
| python3-unbound-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: c375e72a692d626abcf2b8155ad7a394cda62a3505da3cd649313848bca20053 |
| python3-unbound-debuginfo-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 357a11a63d24c8e21c17bcc18327c14bcf2f47a669b7869d563e5ade251a1aa9 |
| python3-unbound-debuginfo-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: 7b9887d3066e183c1ccd9fba753f7c949e7836032d4340187e6f569937057bc7 |
| unbound-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: 445cefd93aaedc5840522f949747f280ec4e568f1f71d443ec5ec525ac3ae361 |
| unbound-debuginfo-1.7.3-15.el8_4.4.i686.rpm | SHA-256: c22fdb6617563b11b7ef32b13148fd51ba11d26664d5c51c8209de34ed71d97a |
| unbound-debuginfo-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: fe5cb68683b71073f70fef17b9a40d980ee561dc4e33d03dc07f3cf1e50eeef1 |
| unbound-debugsource-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 7067e2ea7501dc90b594470c698f74413f7cfe79cbdb3bd8cd29cb937cdc656a |
| unbound-debugsource-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: b3fbbaa3e5b2f1e027b35b04c8aeecd981f804fe35d6ad075cae76add8f36d7d |
| unbound-devel-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 53b73739bdb120002d71f4ca25034497aed52fe65a6cbb7b0cca65019cd1ddf0 |
| unbound-devel-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: aaf28ec1cafed431f0583b2165c3575db0309f21560abbc07e4a57be079de7eb |
| unbound-libs-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 8b4c40bb33933a700e3a5df6b8e9e5e7601d7e1fd372367b55b8d9516efa44f0 |
| unbound-libs-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: d4d5abed59f7ff6531b24f9372afc71e3efaa1fbe081e68a3125cf0b20070abc |
| unbound-libs-debuginfo-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 02a495082c30b9fca6f0b276300d7af175afadea0d4d2533d7ad017ebb780a74 |
| unbound-libs-debuginfo-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: 824a76a03b4776bbedd81999e9bce772f985348d8aa323c04cfd2d416ac79e2c |
Red Hat Enterprise Linux Server - AUS 8.4
| SRPM | |
|---|---|
| unbound-1.7.3-15.el8_4.4.src.rpm | SHA-256: 414d8fd1b1e6e9d4c6f0349eba1edf0b06d7a2bc5b8cded6e8ddcec78d22d4ba |
| x86_64 | |
| python3-unbound-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: c375e72a692d626abcf2b8155ad7a394cda62a3505da3cd649313848bca20053 |
| python3-unbound-debuginfo-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 357a11a63d24c8e21c17bcc18327c14bcf2f47a669b7869d563e5ade251a1aa9 |
| python3-unbound-debuginfo-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: 7b9887d3066e183c1ccd9fba753f7c949e7836032d4340187e6f569937057bc7 |
| unbound-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: 445cefd93aaedc5840522f949747f280ec4e568f1f71d443ec5ec525ac3ae361 |
| unbound-debuginfo-1.7.3-15.el8_4.4.i686.rpm | SHA-256: c22fdb6617563b11b7ef32b13148fd51ba11d26664d5c51c8209de34ed71d97a |
| unbound-debuginfo-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: fe5cb68683b71073f70fef17b9a40d980ee561dc4e33d03dc07f3cf1e50eeef1 |
| unbound-debugsource-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 7067e2ea7501dc90b594470c698f74413f7cfe79cbdb3bd8cd29cb937cdc656a |
| unbound-debugsource-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: b3fbbaa3e5b2f1e027b35b04c8aeecd981f804fe35d6ad075cae76add8f36d7d |
| unbound-devel-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 53b73739bdb120002d71f4ca25034497aed52fe65a6cbb7b0cca65019cd1ddf0 |
| unbound-devel-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: aaf28ec1cafed431f0583b2165c3575db0309f21560abbc07e4a57be079de7eb |
| unbound-libs-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 8b4c40bb33933a700e3a5df6b8e9e5e7601d7e1fd372367b55b8d9516efa44f0 |
| unbound-libs-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: d4d5abed59f7ff6531b24f9372afc71e3efaa1fbe081e68a3125cf0b20070abc |
| unbound-libs-debuginfo-1.7.3-15.el8_4.4.i686.rpm | SHA-256: 02a495082c30b9fca6f0b276300d7af175afadea0d4d2533d7ad017ebb780a74 |
| unbound-libs-debuginfo-1.7.3-15.el8_4.4.x86_64.rpm | SHA-256: 824a76a03b4776bbedd81999e9bce772f985348d8aa323c04cfd2d416ac79e2c |
Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle Long Life 8.4
| SRPM | |
|---|---|
| unbound-1.7.3-15.el8_4.4.src.rpm | SHA-256: 414d8fd1b1e6e9d4c6f0349eba1edf0b06d7a2bc5b8cded6e8ddcec78d22d4ba |
| aarch64 | |
| python3-unbound-1.7.3-15.el8_4.4.aarch64.rpm | SHA-256: d8fd90e1b3336504e369e4dffbcbd92f8665136712ac48db136a58be06c4d3de |
| python3-unbound-debuginfo-1.7.3-15.el8_4.4.aarch64.rpm | SHA-256: 15918fde44e729fbf79adbcb71d9c13eea2e2d0d56877443ef4bf0e4b827f80b |
| unbound-1.7.3-15.el8_4.4.aarch64.rpm | SHA-256: 8a8c91fe0a133051d3e810e0069bc50033e3e17a1a03e3376914b5c75fc89106 |
| unbound-debuginfo-1.7.3-15.el8_4.4.aarch64.rpm | SHA-256: a366780bc64d18d26f82c4635c56bf1a01b4c7a00e17b38f2d020e6c6a2553f6 |
| unbound-debugsource-1.7.3-15.el8_4.4.aarch64.rpm | SHA-256: f981f8a6a13273ea28df51166a47faf1fc24582f9bea0a273b03fc4e1ca61716 |
| unbound-devel-1.7.3-15.el8_4.4.aarch64.rpm | SHA-256: 8c867bca4219fea2cffd6cf0f9da679f2dddf34c8c8f8dc6a16c10f44111f58a |
| unbound-libs-1.7.3-15.el8_4.4.aarch64.rpm | SHA-256: 60705cfbb7e3f55621004ea3267fd92dc44c24ba8984926615479407dbf9c049 |
| unbound-libs-debuginfo-1.7.3-15.el8_4.4.aarch64.rpm | SHA-256: aaf11f2c9d0a6a8c621d10eaca26666467d7fd25c8cd23495d356887dc793f93 |
Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle Long Life 8.4
| SRPM | |
|---|---|
| unbound-1.7.3-15.el8_4.4.src.rpm | SHA-256: 414d8fd1b1e6e9d4c6f0349eba1edf0b06d7a2bc5b8cded6e8ddcec78d22d4ba |
| ppc64le | |
| python3-unbound-1.7.3-15.el8_4.4.ppc64le.rpm | SHA-256: 5cdb83975e69e964a208042c727e64070a5d887972aef4729dc0713f8bf98fec |
| python3-unbound-debuginfo-1.7.3-15.el8_4.4.ppc64le.rpm | SHA-256: 38927adf4d4548d517d3d78e58bb58594a0744535a4a56b83c65dd45e368c0da |
| unbound-1.7.3-15.el8_4.4.ppc64le.rpm | SHA-256: 2eab2ba92a650d65cea46a695131df5be5e9d3dfe8f246894c1fbf77c8742c15 |
| unbound-debuginfo-1.7.3-15.el8_4.4.ppc64le.rpm | SHA-256: e89e8205a0ad3216ec61919f6827c5285d3cf20ad03c6407d8499255e5132e4c |
| unbound-debugsource-1.7.3-15.el8_4.4.ppc64le.rpm | SHA-256: b98e93617d8424799b9eb9dcd5fcc57965a8d582720eac47659eef79acb42192 |
| unbound-devel-1.7.3-15.el8_4.4.ppc64le.rpm | SHA-256: f546aa6d5f925229c1a903ed1a42839f106ea075ba9a92c264297b0f7e9b1abb |
| unbound-libs-1.7.3-15.el8_4.4.ppc64le.rpm | SHA-256: cb6aecee77213a422824b234ba3610d4782c0e4a1adfbe1f9ee773f59a823e52 |
| unbound-libs-debuginfo-1.7.3-15.el8_4.4.ppc64le.rpm | SHA-256: c4c1e5771fc21addac8470cf8fa13ca0099d03b6de36b8815a9dedbf832a8818 |
Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle Long Life 8.4
| SRPM | |
|---|---|
| unbound-1.7.3-15.el8_4.4.src.rpm | SHA-256: 414d8fd1b1e6e9d4c6f0349eba1edf0b06d7a2bc5b8cded6e8ddcec78d22d4ba |
| s390x | |
| python3-unbound-1.7.3-15.el8_4.4.s390x.rpm | SHA-256: 90b52d0fd74467de171c970fd80e18505999788a5756627c647117b98905572a |
| python3-unbound-debuginfo-1.7.3-15.el8_4.4.s390x.rpm | SHA-256: 0416dd499b71634e6359e38baa4884b1bca7c8b1f1d0d2f909634a9cf2243f5b |
| unbound-1.7.3-15.el8_4.4.s390x.rpm | SHA-256: 1d61929c829dd8b55d526559010866a37217f10e8c1b4cc9189f4b8c3b18aeb9 |
| unbound-debuginfo-1.7.3-15.el8_4.4.s390x.rpm | SHA-256: 2515d956c5c133aada2eea23020f62064e89bbcc98cec68ba7fa13b921902d3f |
| unbound-debugsource-1.7.3-15.el8_4.4.s390x.rpm | SHA-256: 84bb973bba3d00f62ca908b2a904f3cba10f03fc870e062c6cfc0ac863913e19 |
| unbound-devel-1.7.3-15.el8_4.4.s390x.rpm | SHA-256: 6430512bf65cf4a0d892fbbb12f2dc82fb1eb149755c2f85f813b5150366bc83 |
| unbound-libs-1.7.3-15.el8_4.4.s390x.rpm | SHA-256: 47b526f9e7b51ccb635e9fc5ed8087056dc23121c9eb68bf91e8edf26616389d |
| unbound-libs-debuginfo-1.7.3-15.el8_4.4.s390x.rpm | SHA-256: eaed3db022169356b1635c91f5f7d82f98a1d4652dee7d94338e3d375c78c425 |
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