{"id":"CVE-2021-31320","aliases":["EUVD-2021-18230","GHSA-6hrw-8fx7-cp46","UBUNTU-CVE-2021-31320","USN-7198-1"],"status":"published","title":"Telegram Android \u003c7.1.0 (2090), Telegram iOS \u003c7.1, and Telegram macOS \u003c7.1 are affected by a Heap...","description":"Telegram Android \u003c7.1.0 (2090), Telegram iOS \u003c7.1, and Telegram macOS \u003c7.1 are affected by a Heap Buffer Overflow in the VGradientCache::generateGradientColorTable function of their custom fork of the rlottie library. A remote attacker might be able to overwrite heap memory out-of-bounds on a victim device via a malicious animated sticker.","severity":{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-09","score":0.01218,"percentile":0.68828,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-787"],"published":"2021-05-18T19:44:14Z","modified":"2026-06-17T03:51:33Z","fixes":[{"ecosystem":"Ubuntu:Pro:20.04:LTS","package":"rlottie","fixed_in":["0~git20200305.a717479+dfsg-1ubuntu0.1~esm1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"rlottie","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0~git20200305.a717479+dfsg-1ubuntu0.1~esm1"}]}],"versions":["0~git20190721.24346d0+dfsg-2","0~git20190721.24346d0+dfsg-2build1","0~git20200305.a717479+dfsg-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"rlottie","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0~git20200305.a717479+dfsg-1ubuntu0.1~esm1"}]}],"versions":["0~git20190721.24346d0+dfsg-2","0~git20190721.24346d0+dfsg-2build1","0~git20200305.a717479+dfsg-1"],"bundled":7},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"rlottie","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.1+dfsg-2ubuntu0.1"}]}],"versions":["0.1+dfsg-2"],"bundled":7}],"products":[{"vendor":"telegram","product":"telegram"}],"references":[{"url":"https://www.shielder.it/blog/2021/02/hunting-for-bugs-in-telegrams-animated-stickers-remote-attack-surface/","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://www.shielder.it/advisories/telegram-rlottie-vgradientcache-generategradientcolortable-heap-buffer-overflow/","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-31320"},{"url":"https://github.com/advisories/GHSA-6hrw-8fx7-cp46"},{"url":"https://ubuntu.com/security/CVE-2021-31320","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-31320","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-7198-1","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-31315","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-31317","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-31318","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-31319","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-31321","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-31322","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-31320","description":"Telegram Android \u003c7.1.0 (2090), Telegram iOS \u003c7.1, and Telegram macOS \u003c7.1 are affected by a Heap Buffer Overflow in the VGradientCache::generateGradientColorTable function of their custom fork of the rlottie library. A remote attacker might be able to overwrite heap memory out-of-bounds on a victim device via a malicious animated sticker.","status":"published","published":"2021-05-18T19:44:14Z","modified":"2024-08-03T22:55:53.487Z","updated_at":"2026-11-02T14:33:05.665371Z"}],"euvd":[{"id":"EUVD-2021-18230","description":"Telegram Android \u003c7.1.0 (2090), Telegram iOS \u003c7.1, and Telegram macOS \u003c7.1 are affected by a Heap Buffer Overflow in the VGradientCache::generateGradientColorTable function of their custom fork of the rlottie library. A remote attacker might be able to overwrite heap memory out-of-bounds on a victim device via a malicious animated sticker.","status":"published","published":"2021-05-18T19:44:14Z","modified":"2024-08-03T22:55:53Z","updated_at":"2026-11-03T03:24:39.559154Z"}],"ghsa":[{"id":"GHSA-6hrw-8fx7-cp46","title":"Telegram Android \u003c7.1.0 (2090), Telegram iOS \u003c7.1, and Telegram macOS \u003c7.1 are affected by a Heap...","description":"Telegram Android \u003c7.1.0 (2090), Telegram iOS \u003c7.1, and Telegram macOS \u003c7.1 are affected by a Heap Buffer Overflow in the VGradientCache::generateGradientColorTable function of their custom fork of the rlottie library. A remote attacker might be able to overwrite heap memory out-of-bounds on a victim device via a malicious animated sticker.","status":"published","published":"2022-05-24T19:02:40Z","modified":"2023-01-29T05:06:44Z","cwes":["CWE-787"],"updated_at":"2026-11-02T14:46:05.419939Z"}],"nvd":[{"id":"CVE-2021-31320","description":"Telegram Android \u003c7.1.0 (2090), Telegram iOS \u003c7.1, and Telegram macOS \u003c7.1 are affected by a Heap Buffer Overflow in the VGradientCache::generateGradientColorTable function of their custom fork of the rlottie library. A remote attacker might be able to overwrite heap memory out-of-bounds on a victim device via a malicious animated sticker.","status":"published","published":"2021-05-18T20:15:07.753Z","modified":"2026-06-17T03:51:33.147Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5.8,"vector":"AV:N/AC:M/Au:N/C:N/I:P/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T14:06:53.343329Z"}],"osv":[{"id":"UBUNTU-CVE-2021-31320","description":"Telegram Android \u003c7.1.0 (2090), Telegram iOS \u003c7.1, and Telegram macOS \u003c7.1 are affected by a Heap Buffer Overflow in the VGradientCache::generateGradientColorTable function of their custom fork of the rlottie library. A remote attacker might be able to overwrite heap memory out-of-bounds on a victim device via a malicious animated sticker.","status":"published","published":"2021-05-18T20:15:00Z","modified":"2026-04-22T12:53:08.972651Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:54:27.332852Z"},{"id":"USN-7198-1","title":"rlottie vulnerabilities","description":"\nPaolo Giai discovered a series of stack-based overflow vulnerabilities in\nthe blit and gray_render_cubic functions of a custom fork of the rlottie\nlibrary. An attacker could possibly use this issue to leak sensitive \ninformation. This issue only affected Ubuntu 20.04 LTS and Ubuntu 22.04\nLTS. (CVE-2021-31315, CVE-2021-31321)\n\nPaolo Giai discovered a series of type confusion vulnerabilities in the\nVDasher constructor and the LOTCompLayerItem::LOTCompLayerItem function\nof a custom fork of the rlottie library. An attacker could possibly use\nthis issue to leak sensitive information. This issue only affected Ubuntu\n20.04 LTS. (CVE-2021-31317, CVE-2021-31318)\n\nPaolo Giai discovered an integer overflow vulnerability in the \nLOTGradient::populate function of a custom fork of the rlottie library.\nAn attacker could possibly use this issue to leak sensitive information.\nThis issue only affected Ubuntu 20.04 LTS. (CVE-2021-31319)\n\nPaolo Giai discovered a series of heap buffer overflow vulnerabilities\nin the VGradientCache::generateGradientColorTable and\nLOTGradient::populate functions of a custom fork of the rlottie library.\nAn attacker could possibly use this issue to achieve remote code execution.\nThis issue only affected Ubuntu 20.04 LTS. (CVE-2021-31320, CVE-2021-31322)\n","status":"published","published":"2025-01-10T01:11:01Z","modified":"2026-04-22T10:48:27.496604Z","updated_at":"2026-11-02T16:58:18.876384Z"}]}}