Malicious PDF — malware analysis report

Static analysis result for SHA-256 aaab35c5f3a45298…

MALICIOUS

PDF

83.2 KB Created: 2021-09-17 14:50:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5d57ebc76d043c914142e90ed03da8cb SHA-1: 49ae287059d8ad445357d6e965a97cfd827ff70c SHA-256: aaab35c5f3a45298ebe5248c3f609a1be3cb9194728867234ab626c0820327f4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to PDF files hosted on potentially compromised websites, suggesting a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination or distribute malicious content across many domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16139bbbdce63e---30032264126.pdf In PDF document text
    • http://slhospital.com/upload/fckeditor/file/varesogesebilupimuk.pdfIn PDF document text
    • https://iasvn.org/Images_upload/files/67694699069.pdfIn PDF document text
    • https://bodykneadstherapy.com.au/ckfinder/userfiles/files/gaviguvinogagegokoxexiga.pdfIn PDF document text
    • http://www.atccs3.it/atccs3/fckeditor/editor/ckfinder/userfiles/files/63894402890.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/cmaod73j09hs0c533j0fppmfp7/90686726514.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/4327660757.pdfIn PDF document text
    • http://svazekobciorlice.cz/userfiles/file/60651136772.pdfIn PDF document text
    • https://gencatakan.com/upload/file/93888695687.pdfIn PDF document text
    • http://icbiz.ru/userfiles/file/34009797393.pdfIn PDF document text
    • http://klubbelgickychobrov.sk/editor_uploads/files/peniwinotatolu.pdfIn PDF document text
    • http://bankerz.in/qpic/files/tolebujivebade.pdfIn PDF document text
    • https://foodvellythailand.com/upload/files/mufodovodewabojubelupa.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/baligapagumokax.pdfIn PDF document text
    • http://huanghels.com/filespath/files/20210910174423.pdfIn PDF document text
    • http://vocal.bpv.su/content/files/files/tidorumutebo.pdfIn PDF document text
    • https://maintogelonline2.bet/contents/files/xazomogal.pdfIn PDF document text
    • http://olgapolyakova.com/files/files/19334366974.pdfIn PDF document text
    • http://abwbaltimore.com/uploads/files/45714668171.pdfIn PDF document text
    • http://metabolizmusonline.hu/images/upload/file/70284059363.pdfIn PDF document text
    • http://defhjdr.friend-match.com/upload/files/ramebilolawuxoxetupad.pdfIn PDF document text
    • http://novafish.it/userfiles/files/pojamegekofonofuranot.pdfIn PDF document text
    • http://hoanggiaphatstone.com/upload/files/vosigimewizuka.pdfIn PDF document text
    • https://adikketiga.com/contents/files/99431679039.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=gel%C3%B6schter+whatsapp+chat+wiederherstellen+androidPDF link annotation
    • 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_off0000d9e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E2 10952 bytes
SHA-256: 24dc1e86c6d09f1c901fedd47c05b3e5a05661d0189af2e1f4e1e08f30c52210
font_01_sfnt_off0000f2f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B09 19736 bytes
SHA-256: 849fd606466acc03d967814446c14f586cb10575da3fc2bcfb33e88a21eea557