Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5165cbbabdaee92…

MALICIOUS

PDF

75.7 KB Created: 2021-09-20 09:51:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5f1c05d57fe62d86fafdcf558f9f05ee SHA-1: 80d2e15ec6b740c5204eff31ff5c1eb3b3bb8f8a SHA-256: b5165cbbabdaee92e3648f48c74f473020c81f0bb9c8a00212a59d5a261484bb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to compromised WordPress uploads and disposable hosting, indicating an attempt to redirect users to malicious sites. The ClamAV detection and ML classifier further support its malicious nature, likely serving as a phishing lure or a downloader for further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://cructi.ru/uplcv?utm_term=android+change+microphone
    • https://mertlakustika.cz/images/pages/file/xiliduzotogizudaf.pdf
    • http://rlangkhan.com/upload/userfiles/files/sepowuj.pdf
    • https://actor-conseil.com/files/file/ladusuperedofaxadajev.pdf
    • https://dgssu.com/upfolder/e/files/20210901215744.pdf
    • http://uniontsg96.ru/admin/ckfinder/userfiles/files/bovulikuwokuzadobonekag.pdf
    • https://asiantms.com/ckfinder/userfiles/files/marunefumafojupepawujome.pdf
    • http://itagqatar.com/itag/file/files/82043531153.pdf
    • http://steakpluspizza.us/userfiles/file/wanamejuwaze.pdf
    • http://feuerwehrobrigheim.de/upload/files/nonanelilej.pdf
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/xipufodabegizavo.pdf
    • https://webaprint.be/img/file/38455097983.pdf
    • http://zkqzl.com/uploadfile/file///2021090106571449.pdf
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/vi5qlp5eco7et7m5i5jeo70dm1/94732519413.pdf
    • http://quranday.org/userfiles/file/69921193940.pdf
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138925de2530---femewufevara.pdf
    • http://abcbyspu.com/ckfinder/images_store/files/xutemenutekadofomazan.pdf
    • http://nhatngungoisaoxanh.com/upload/files/87950396342.pdf
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/87cfcf3f85f2c27c1696d05ab5697bc3/46558776858.pdf
    • http://studiodugnani.it/userfiles/files/7532076940.pdf
    • http://446888.top/userfiles/file/47724859984.pdf
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16132869adbad2---zepunonujiduzalekesa.pdf
    • http://www.ks-klinika.ru/ckfinder/userfiles/files/66871158973.pdf
    • https://pmcp-avac.com/files/upload-ckfinder/files/sozarij.pdf
    • http://gopherandsquirrelcontrol.com/admin/images/file/61223395144.pdf
    • http://livelyway.com/ckfinder/userfiles/files/17352776864.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c718.bin
6a95b54d91467f6877db29513c3cfcaf01e4169a1f3d63680a3efadf5bbc6373
pdf-font-stream PDF embedded font (sfnt) at offset 0xC718 16496 bytes
font_01_sfnt_off0000f170.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF170 16792 bytes
font_02_sfnt_off00010987.bin
f2e92bb4f786dd5df87c6e47e63e61786613a3c0981fb9b04a06f0c0e1032ddd
pdf-font-stream PDF embedded font (sfnt) at offset 0x10987 10628 bytes