Malicious PDF — malware analysis report

Static analysis result for SHA-256 50b5b1de6bc7cad8…

MALICIOUS

PDF

69.0 KB Created: 2021-09-26 22:25:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b4ce33a03a500f49cda6e17d07d99483 SHA-1: d53ac9c0da1511bbb4a4f127cbf6de37e6f9e6e4 SHA-256: 50b5b1de6bc7cad8a5948d05989b6582f8d38245363ca894ac83a262b0fbb7a1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was detected as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting and are part of a link farm, a common tactic for distributing malware or conducting phishing campaigns. The PDF's structure and the presence of many external links strongly suggest it's designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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=how+to+see+archived+messages+on+android PDF link annotation
    • http://www.andreapondika.cz/file/66150382766.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137ee9c763cd---8343408333.pdfIn PDF document text
    • http://gniortho.com/files/Upload/file/95210492778.pdfIn PDF document text
    • https://dottoridegregorio.it/public/file/34137433609.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/vofazitido.pdfIn PDF document text
    • https://minhgianggroup.vn/upload/files/78772932438.pdfIn PDF document text
    • http://zkojicin.cz/userfiles/file/raxemapomux.pdfIn PDF document text
    • https://ph789.com/pinhsuan/files/file/45090680082.pdfIn PDF document text
    • http://impressivetravelvietnam.com/upload/files/70140714996.pdfIn PDF document text
    • https://maconlux.lu/userfiles/files/61168549485.pdfIn PDF document text
    • http://nfc-lampang.com/user_img/files/jujuxoxadadutusegus.pdfIn PDF document text
    • http://cs-web-design.de/ablage/userfiles/files/51066825588.pdfIn PDF document text
    • https://ln80.cn/filespath/files/20210925100953.pdfIn PDF document text
    • http://www.yevres.fr/ckfinder/userfiles/files/modojimesexakezunoduwelip.pdfIn PDF document text
    • http://olgapolyakova.de/files/files/voroliwulufovevubex.pdfIn PDF document text
    • https://ngonluathan.com/images/ckeditor/files/paroxobir.pdfIn PDF document text
    • http://lungshingcentre.com/userfiles/tesawefubukajolunusirexo.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/ncqoag6g8k4ipu4nq5v7vqmdas/45220820575.pdfIn PDF document text
    • https://maychieuvinh.vn/upload/files/jobelujilanaleledabu.pdfIn PDF document text
    • http://emannsltd.com/userfiles/wakigejox.pdfIn PDF document text
    • https://eguiders.com/uploads/pobojenajuvu.pdfIn PDF document text
    • http://islaminkiel.de/webmisr/uploadwebmisr/file/wapewiwesomixor.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b066.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB066 10916 bytes
SHA-256: 4da3489d9841d516159fe4339649454747f84d9704c70ff372ab88af254b1745
font_01_sfnt_off0000c954.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC954 14784 bytes
SHA-256: 38bc34bcd4bcf7f8138c7b37750eacfc6973d29cf3d2dfe8f4ef29a4c0241da9
font_02_sfnt_off0000ee63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE63 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1