Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf1dfb39e5891d16…

MALICIOUS

PDF

106.5 KB Created: 2021-06-30 16:50:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 418a1dd79f8dc8d26e2ab4d556767e02 SHA-1: 0df8035ce172681e2b67f8709b61d53a3bd15e51 SHA-256: bf1dfb39e5891d160166358e0738de0cdf1844570d74c7567293a6da28566215
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the PDF structure itself is used to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 https://seitonsolutions.com/ci/files/14350065636.pdf
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/11ad157f58408b38713776d2cda8852e/zijisuralejoxuxi.pdf
    • https://ctapigroup3.com/contents//files/vudirizupofip.pdf
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/k7t3cdee7c2nvdiocaufvdejna/17497320975.pdf
    • https://branchennachweis.eu/userfiles/file/75109896480.pdf
    • https://ambulatorioveterinariosismondi.eu/file/vofenivosabokozebonunek.pdf
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/366185ac254683738d67206ef0e1e038/10616848050.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ac93c432d99---koxumasewo.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087db86821a5---16890145577.pdf
    • http://gdgom.com/upload/file/210613195257752698mekcydkxwn5e.pdf
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c46f8660b95---59243785177.pdf
    • https://shipnhanh247.vn/asset/files/10508991715.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607abdd65d9f2---nawuvagokakanalivife.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/d33ae98e2627c09878ac85ff238c41a8/rabip.pdf
    • http://okmarin.ru/userfiles/file/81996814859.pdf
    • http://goteneplast.se/files/images/file/motetuzunalubafiva.pdf
    • http://provia-events.de/pics/fotos/1/file/mesodekibin.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609fc1bfb3d83---nodadedomogazewiwixomiko.pdf
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608bbd7fd20ce---109340042.pdf
    • http://tomnhenryanderson.com/clients/8/8a/8a1068334c160bb49438aafe8043afff/File/wupodita.pdf
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c97cecc6c7b---gemivuj.pdf
    • http://dribblebar.pl/userfiles/file/malupowenexigi.pdf
    • http://murielbellhomes.com/userfiles/files/vumivoxikadetedozego.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=reticular+pulmonary+infiltrates
    • 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_off00013f60.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F60 16792 bytes
font_01_sfnt_off00015777.bin
32b93947e7c667cf7ff0576b8757eb77762fa57707171675aed7679b83ebecae
pdf-font-stream PDF embedded font (sfnt) at offset 0x15777 10900 bytes
font_02_sfnt_off000170bb.bin
31e8fe8ee2408c4e9006a30abcc7b03c1c9d1ed112aed3ad6cc8f89ef9d4a1a9
pdf-font-stream PDF embedded font (sfnt) at offset 0x170BB 16864 bytes