Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3f874eb2ecf48c2…

MALICIOUS

PDF

80.1 KB Created: 2021-09-19 14:30:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1789690052c7330efb278a19becf8010 SHA-1: 4831153d4e50bad67ee9cab61f132d16edba68d9 SHA-256: b3f874eb2ecf48c2c27067b6b314a6e7ae3789ffb85be6dbce8575df952d506d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to compromised WordPress uploads and disposable hosting, likely to distribute phishing content or further malware. The embedded URLs are the primary indicators of compromise, suggesting the document's purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://nomylo.ru/uplcv?utm_term=how+to+share+files+between+windows+and+android PDF link annotation
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/0e7aa07a08090beb63c231d8ec6e249e/55625433145.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/nemewipa.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1d03849abce68ff2b104f4e9b20e6f74/16123196710.pdfIn PDF document text
    • https://granitabrasive.ro/editor_up/60138957185.pdfIn PDF document text
    • http://terwaarde.be/ckfinder/userfiles/files/bisuwujeba.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/mqgp4e8hhs7030e8iu4sorqso3/winesaxadetipuwu.pdfIn PDF document text
    • http://thibidi.vinadesign.info/uploads/images/files/tusapaguzofafixo.pdfIn PDF document text
    • https://sonerofset.com/userfiles/file/77298662686.pdfIn PDF document text
    • https://weekendtripskolkata.com/userfiles/file/gerujipubanidiliboluzop.pdfIn PDF document text
    • http://hydrem.ru/images/file/86647473506.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/63228621782.pdfIn PDF document text
    • http://villalapinetafavignana.it/userfiles/files/dejemegesugagerilizaje.pdfIn PDF document text
    • http://micruts.org/userfiles/file/80108046741.pdfIn PDF document text
    • https://mimpiindah88.com/contents/files/lobatugasoxasoti.pdfIn PDF document text
    • http://acevina.com/webroot/img/files/93557207376.pdfIn PDF document text
    • http://narnivet.com/userfiles/files/78971534839.pdfIn PDF document text
    • http://rlponder.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/32407985359.pdfIn PDF document text
    • https://e-ssuances.com/ckfinder/userfiles/files/pepelizuxozip.pdfIn PDF document text
    • http://fitviewer.info/files/file/1001330383.pdfIn PDF document text
    • http://uklearningnetwork.com/userfiles/file/zazosonopazuzibaf.pdfIn PDF document text
    • https://jancsoalapitvany.hu/ckfinder/userfiles/files/dasanude.pdfIn PDF document text
    • http://belean.pl/userfiles/file/39819019787.pdfIn PDF document text
    • https://listapp.in/ci/userfiles/files/58974229707.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_off0000d5fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5FA 17152 bytes
SHA-256: 85cc5b12dbec7b8e23b1770b21091411b9dac0e5c229e393556fc0a2956ae925
font_01_sfnt_off0001020e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1020E 10668 bytes
SHA-256: 6f431a4202043fd117d1867711b788290614ec2dbdd02b8d54aa8f1fb0426aa0
font_02_sfnt_off00011a6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A6C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1