Malicious PDF — malware analysis report

Static analysis result for SHA-256 844d56fd022b3dab…

MALICIOUS

PDF

73.1 KB Created: 2021-06-24 14:47:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 0a6fd22d9860e6cd806bc1be650a8c81 SHA-1: 13f9f7327a31f6ef3f8da398a364a525a7fa1942 SHA-256: 844d56fd022b3dab6fc1beb40e5229c3e83d91776697125d15ed9481631e7362
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and link farm heuristics strongly suggest it's part of a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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.
  • 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://albatrossmrn.com/konadnew/userfiles/file/96072294650.pdf In PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/59b208487ee2c64550f8050e820dca8c/xavezuroza.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f36450e3be---54319280683.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608031dae72cf---dedajebipob.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a910545ee8c---97459961042.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609013c7d21ac---57226480881.pdfIn PDF document text
    • https://vestol.bg/files/file/43745429350.pdfIn PDF document text
    • http://chi-kara.net/userfiles/file/93232979415.pdfIn PDF document text
    • http://bakoca.hu/files/file/xeziwaxavudilivivirowi.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/73bb5931abab0c365fd8ca5181bf0024/mujexub.pdfIn PDF document text
    • https://goldenapp.net/file/jadadirikokoferofo.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/f07fe53780f3eada185bd80159f7453d/91521752824.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/lafiwuwosivol.pdfIn PDF document text
    • https://olgapopovaphoto.com/wp-content/plugins/super-forms/uploads/php/files/564575d38b83c7fff3b0741240eb2fb0/dibekoxilo.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca48aab2d63---polilexaleropuronekud.pdfIn PDF document text
    • http://cohensevents.com/clients/74638/File/rerikunuzifemugune.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=mix+design+of+concrete+is+codePDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e0bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0BF 5020 bytes
SHA-256: d7b1f00988a8ab579c01e4f3e19483dd08cd02fac26ebfc7fb4f00cc3718e5f4
font_01_sfnt_off0000f1fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FA 11072 bytes
SHA-256: 7898ed73297cd3c9eae4420a20ae19614b5ec5c48ad68315b247695570123e8d