From 08a5882d96cae90c7a8b785e30d4028f072975b7 Mon Sep 17 00:00:00 2001 From: Ankur Tyagi Date: Wed, 21 Oct 2026 00:03:54 +1300 Subject: [PATCH] libvncserver: patch CVE-2026-44988 Details: https://nvd.nist.gov/vuln/detail/cve-2026-44988 Signed-off-by: Ankur Tyagi Signed-off-by: Khem Raj --- .../libvncserver/CVE-2026-44988.patch | 71 +++++++++++++++++++ .../libvncserver/libvncserver_0.9.15.bb | 1 + 2 files changed, 72 insertions(+) create mode 100644 meta-oe/recipes-graphics/libvncserver/libvncserver/CVE-2026-44988.patch diff --git a/meta-oe/recipes-graphics/libvncserver/libvncserver/CVE-2026-44988.patch b/meta-oe/recipes-graphics/libvncserver/libvncserver/CVE-2026-44988.patch new file mode 100644 index 0000000000..e26abc9db7 --- /dev/null +++ b/meta-oe/recipes-graphics/libvncserver/libvncserver/CVE-2026-44988.patch @@ -0,0 +1,71 @@ +From db5779f2bec717f577fb66321b3b079ff156da95 Mon Sep 17 00:00:00 2001 +From: Kang Hee chan <24s101h0659@sonline20.sen.go.kr> +Date: Wed, 6 May 2026 21:48:54 +0900 +Subject: [PATCH] libvncclient: fix Tight gradient decoding overflow + +(cherry picked from commit 5b270544b85233668b98161323297d418a8f5fd1) + +CVE: CVE-2026-44988 +Upstream-Status: Backport [https://github.com/LibVNC/libvncserver/commit/5b270544b85233668b98161323297d418a8f5fd1] +Signed-off-by: Ankur Tyagi +--- + include/rfb/rfbclient.h | 3 ++- + src/libvncclient/tight.c | 10 +++++++--- + 2 files changed, 9 insertions(+), 4 deletions(-) + +diff --git a/include/rfb/rfbclient.h b/include/rfb/rfbclient.h +index a974ff5f..666dcb90 100644 +--- a/include/rfb/rfbclient.h ++++ b/include/rfb/rfbclient.h +@@ -314,10 +314,11 @@ typedef struct _rfbClient { + rfbBool zlibStreamActive[4]; + + /* Filter stuff. Should be initialized by filter initialization code. */ ++#define TIGHT_GRADIENT_MAX_WIDTH 2048 + rfbBool cutZeros; + int rectWidth, rectColors; + char tightPalette[256*4]; +- uint8_t tightPrevRow[2048*3*sizeof(uint16_t)]; ++ uint8_t tightPrevRow[TIGHT_GRADIENT_MAX_WIDTH*3*sizeof(uint16_t)]; + + #ifdef LIBVNCSERVER_HAVE_LIBJPEG + /** JPEG decoder state (obsolete-- do not use). */ +diff --git a/src/libvncclient/tight.c b/src/libvncclient/tight.c +index 57a3715b..dad5514f 100644 +--- a/src/libvncclient/tight.c ++++ b/src/libvncclient/tight.c +@@ -229,6 +229,11 @@ HandleTightBPP (rfbClient* client, int rx, int ry, int rw, int rh) + bitsPixel = InitFilterPaletteBPP(client, rw, rh); + break; + case rfbTightFilterGradient: ++ if (rw > TIGHT_GRADIENT_MAX_WIDTH) { ++ rfbClientLog("Tight Gradient rectangle width %d exceeds maximum %d.\n", ++ rw, TIGHT_GRADIENT_MAX_WIDTH); ++ return FALSE; ++ } + filterFn = FilterGradientBPP; + bitsPixel = InitFilterGradientBPP(client, rw, rh); + break; +@@ -430,7 +435,7 @@ FilterGradient24 (rfbClient* client, int srcx, int srcy, int numRows) + CARDBPP *dst = + (CARDBPP *)&client->frameBuffer[(srcy * client->width + srcx) * BPP / 8]; + int x, y, c; +- uint8_t thisRow[2048*3]; ++ uint8_t thisRow[TIGHT_GRADIENT_MAX_WIDTH*3]; + uint8_t pix[3]; + int est[3]; + +@@ -473,7 +478,7 @@ FilterGradientBPP (rfbClient* client, int srcx, int srcy, int numRows) + int x, y, c; + CARDBPP *src = (CARDBPP *)client->buffer; + uint16_t *thatRow = (uint16_t *)client->tightPrevRow; +- uint16_t thisRow[2048*3]; ++ uint16_t thisRow[TIGHT_GRADIENT_MAX_WIDTH*3]; + uint16_t pix[3]; + uint16_t max[3]; + int shift[3]; +@@ -705,4 +710,3 @@ ReadCompactLen (rfbClient* client) + /* LIBVNCSERVER_HAVE_LIBZ and LIBVNCSERVER_HAVE_LIBJPEG */ + #endif + #endif +- diff --git a/meta-oe/recipes-graphics/libvncserver/libvncserver_0.9.15.bb b/meta-oe/recipes-graphics/libvncserver/libvncserver_0.9.15.bb index 77612e1626..47e42cd094 100644 --- a/meta-oe/recipes-graphics/libvncserver/libvncserver_0.9.15.bb +++ b/meta-oe/recipes-graphics/libvncserver/libvncserver_0.9.15.bb @@ -46,6 +46,7 @@ inherit cmake pkgconfig SRC_URI = "git://github.com/LibVNC/libvncserver;branch=master;protocol=https;tag=LibVNCServer-${PV} \ file://0001-CMake-require-at-least-CMake-3.5.patch \ + file://CVE-2026-44988.patch \ " SRCREV = "9b54b1ec32731bd23158ca014dc18014db4194c3"