Red Hat Product Errata RHSA-2026:27742 - Security Advisory Issued: 2026-06-22 Updated: 2026-06-22 RHSA-2026:27742 - Security Advisory Overview Updated Packages Synopsis Important: postgresql18 security update Type/Severity Security Advisory: Important Red Hat Lightspeed patch analysis Identify and remediate systems affected by this advisory. View affected systems Topic An update for postgresql18 is now available for Red Hat Enterprise Linux 10. Red Hat Product Security has rated this update as having a security impact of Important. 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 PostgreSQL is an advanced Object-Relational database management system (DBMS). The base postgresql package contains the client programs that you'll need to access a PostgreSQL DBMS server, as well as HTML documentation for the whole system. These client programs can be located on the same machine as the PostgreSQL server, or on a remote machine that accesses a PostgreSQL server over a network connection. The PostgreSQL server can be found in the postgresql-server sub-package. Security Fix(es): postgresql: PostgreSQL: Operating system account hijack via symlink following in pg_basebackup and pg_rewind (CVE-2026-6475) postgresql: PostgreSQL libpq: Buffer overflow allows server superuser to overwrite client stack memory (CVE-2026-6477) postgresql: PostgreSQL: Credential recovery via covert timing channel in MD5 password comparison (CVE-2026-6478) postgresql: integer overflow can cause an undersized allocation and an out-of-bounds write (CVE-2026-6473) 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: https://access.redhat.com/articles/11258 Affected Products Red Hat Enterprise Linux for x86_64 10 x86_64 Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.2 x86_64 Red Hat Enterprise Linux for IBM z Systems 10 s390x Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.2 s390x Red Hat Enterprise Linux for Power, little endian 10 ppc64le Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.2 ppc64le Red Hat Enterprise Linux for ARM 64 10 aarch64 Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.2 aarch64 Red Hat CodeReady Linux Builder for x86_64 10 x86_64 Red Hat CodeReady Linux Builder for Power, little endian 10 ppc64le Red Hat CodeReady Linux Builder for ARM 64 10 aarch64 Red Hat CodeReady Linux Builder for IBM z Systems 10 s390x Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 10.2 x86_64 Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 10.2 ppc64le Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 10.2 s390x Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 10.2 aarch64 Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.2 aarch64 Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.2 s390x Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.2 ppc64le Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.2 x86_64 Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 10.2 x86_64 Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 10.2 aarch64 Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 10.2 ppc64le Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 10.2 s390x Fixes BZ - 2477439 - CVE-2026-6475 postgresql: PostgreSQL: Operating system account hijack via symlink following in pg_basebackup and pg_rewind BZ - 2477442 - CVE-2026-6477 postgresql: PostgreSQL libpq: Buffer overflow allows server superuser to overwrite client stack memory BZ - 2477447 - CVE-2026-6478 postgresql: PostgreSQL: Credential recovery via covert timing channel in MD5 password comparison BZ - 2477448 - CVE-2026-6473 postgresql: integer overflow can cause an undersized allocation and an out-of-bounds write CVEs CVE-2026-6473 CVE-2026-6475 CVE-2026-6477 CVE-2026-6478 References https://access.redhat.com/security/updates/classification/#important Note: More recent versions of these packages may be available. Click a package name for more details. Red Hat Enterprise Linux for x86_64 10 SRPM postgresql18-18.4-1.el10_2.src.rpm SHA-256: b2bf43e5024c63daa6b74b92a46c3bc8076df7681bcbb1a289d62e634dfe6a78 x86_64 postgresql18-18.4-1.el10_2.x86_64.rpm SHA-256: 79c509a5099921c49db5ea48e0a390ceacd724ea601bdf9926cc596bee2fa631 postgresql18-contrib-18.4-1.el10_2.x86_64.rpm SHA-256: ecc331057ea12b3b7b5e16c8bc3cbc0e532cf7d13ddfd770b6e92c2f24276331 postgresql18-contrib-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 5eb50f544952e6fb98c955245859600d723369e1f830a7a924d71312663adf8d postgresql18-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 233f0c0191dac7b420c79b2bf1d714dd468542dccff462c1f059bb9639555993 postgresql18-debugsource-18.4-1.el10_2.x86_64.rpm SHA-256: 6ec44f35e38d6deb146e69789cce77d5fb20a16f2d423d09e1ada303401b2f91 postgresql18-docs-18.4-1.el10_2.x86_64.rpm SHA-256: 8fb33a227108b843a413f5517bbad7b4814979c3c4041e2401bc80d3f69e87d7 postgresql18-docs-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 0f3a06127aef2e0fcd141a7bcbc6e29b40bf33a27aee92ed5439bd2b5490bdbd postgresql18-plperl-18.4-1.el10_2.x86_64.rpm SHA-256: 967b85a2dc507b6feec1314583e9b8ad5bdecbe060d48ce5e2ca019a848ecd33 postgresql18-plperl-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: ebc9b05eb1af470bac8ab57a7cca86c58084d138dfed88d892a633aafe4e4aac postgresql18-plpython3-18.4-1.el10_2.x86_64.rpm SHA-256: e865ef943dd5c108c53ad7b7a986731ff0005bef3527bfdd2bab119938ba69c4 postgresql18-plpython3-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 3e9f6438e58838a3640d9ddef4023d087e6cbba67c62b700ddb2d849e9e7e929 postgresql18-pltcl-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 80c81dc43c8f6eba8340c6f1e3fba26b9cdac273b0df814dc00b1aa49682effe postgresql18-private-devel-18.4-1.el10_2.x86_64.rpm SHA-256: aec7cd5d84db41ec72e99f687d3d8d7ab5a22ed20ebbe6fed2bdb4b3372c958f postgresql18-private-libs-18.4-1.el10_2.x86_64.rpm SHA-256: 22c93c78d04f91ed65df25db8da08a5cf960ae3b40fc7171bc52ea4ea950f15f postgresql18-private-libs-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: f407ef0f7bb09bf7b6ceda4760f12d383d2ad37c39cc93caa0db3a070f4d826b postgresql18-server-18.4-1.el10_2.x86_64.rpm SHA-256: 9cb647a67ea6e8cb4e8af101b75b5b55671ab2f132528d820bb7f1ef013f83a2 postgresql18-server-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 33439c559e60b932089456bdbb6c53526d1c5f1789d860c1dc80505ca8e0e5f0 postgresql18-server-devel-18.4-1.el10_2.x86_64.rpm SHA-256: 1bd2a777d4c7a91a42f2192234c62148e99b6697d660981ec0f630bc57f276a5 postgresql18-server-devel-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: c6771cda7fd14fdacfd1a4188936fbf25cb05d1f9c588b66616c3a960594cfb0 postgresql18-static-18.4-1.el10_2.x86_64.rpm SHA-256: d4141913951235fcb694a8a407058ee97d8bcf4cf64b3944c3da0f242a4767cd postgresql18-test-18.4-1.el10_2.x86_64.rpm SHA-256: ea8c50373a545fb515c9848037e0c157300e07c00efb0ff886809f73a37f160c postgresql18-test-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 9e00aff36770023de31fbf46e3b5896b621a30eae950f61e65b9d0a089d47470 postgresql18-upgrade-18.4-1.el10_2.x86_64.rpm SHA-256: 2fe6ed2a2b2c3209045ea892af55c7af1922c35b1250c9d24f38fe86a8a3215a postgresql18-upgrade-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 39b8a7e92e15d26534dd7574dfd053afa1e0789c36ebf5a2750d04e4cc7f87b7 postgresql18-upgrade-devel-18.4-1.el10_2.x86_64.rpm SHA-256: 1848f5fee6bd5cf1c3903017b5b6c098cf71db1e195a6d0f32dd0317d60d394a postgresql18-upgrade-devel-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 4aa89d3770e891fe751ffa2ec36b508d2a792124805cd804e0d2fde5142d7eef Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.2 SRPM postgresql18-18.4-1.el10_2.src.rpm SHA-256: b2bf43e5024c63daa6b74b92a46c3bc8076df7681bcbb1a289d62e634dfe6a78 x86_64 postgresql18-18.4-1.el10_2.x86_64.rpm SHA-256: 79c509a5099921c49db5ea48e0a390ceacd724ea601bdf9926cc596bee2fa631 postgresql18-contrib-18.4-1.el10_2.x86_64.rpm SHA-256: ecc331057ea12b3b7b5e16c8bc3cbc0e532cf7d13ddfd770b6e92c2f24276331 postgresql18-contrib-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 5eb50f544952e6fb98c955245859600d723369e1f830a7a924d71312663adf8d postgresql18-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 233f0c0191dac7b420c79b2bf1d714dd468542dccff462c1f059bb9639555993 postgresql18-debugsource-18.4-1.el10_2.x86_64.rpm SHA-256: 6ec44f35e38d6deb146e69789cce77d5fb20a16f2d423d09e1ada303401b2f91 postgresql18-docs-18.4-1.el10_2.x86_64.rpm SHA-256: 8fb33a227108b843a413f5517bbad7b4814979c3c4041e2401bc80d3f69e87d7 postgresql18-docs-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 0f3a06127aef2e0fcd141a7bcbc6e29b40bf33a27aee92ed5439bd2b5490bdbd postgresql18-plperl-18.4-1.el10_2.x86_64.rpm SHA-256: 967b85a2dc507b6feec1314583e9b8ad5bdecbe060d48ce5e2ca019a848ecd33 postgresql18-plperl-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: ebc9b05eb1af470bac8ab57a7cca86c58084d138dfed88d892a633aafe4e4aac postgresql18-plpython3-18.4-1.el10_2.x86_64.rpm SHA-256: e865ef943dd5c108c53ad7b7a986731ff0005bef3527bfdd2bab119938ba69c4 postgresql18-plpython3-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 3e9f6438e58838a3640d9ddef4023d087e6cbba67c62b700ddb2d849e9e7e929 postgresql18-pltcl-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: 80c81dc43c8f6eba8340c6f1e3fba26b9cdac273b0df814dc00b1aa49682effe postgresql18-private-devel-18.4-1.el10_2.x86_64.rpm SHA-256: aec7cd5d84db41ec72e99f687d3d8d7ab5a22ed20ebbe6fed2bdb4b3372c958f postgresql18-private-libs-18.4-1.el10_2.x86_64.rpm SHA-256: 22c93c78d04f91ed65df25db8da08a5cf960ae3b40fc7171bc52ea4ea950f15f postgresql18-private-libs-debuginfo-18.4-1.el10_2.x86_64.rpm SHA-256: f407ef0f7bb09bf7b6ceda4760f12d383d2ad37c39cc93caa0db3a070f4d826b postgre