Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd3a067b27ac925a…

MALICIOUS

PDF

78.5 KB Created: 2021-09-24 03:10:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 566598825f10d761bd24e652d27e2e30 SHA-1: 04434e88c2df5058208d9ed7c8f3dac32761a28a SHA-256: fd3a067b27ac925aa7fa584920b558d0ee5faa05cd3b4693ccbf25a24fb2fcd6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains a large number of embedded URLs pointing to various domains, suggesting a link farm or phishing campaign. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags the document as a link farm on disposable hosting, reinforcing the phishing or malware distribution attack pattern. No scripts were extracted, but the sheer volume of external links is the primary indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://irlanc.ru/uplcv?utm_term=luke+16+commentary+easy+english PDF link annotation
    • http://xn--d1achljw0b.xn--p1ai/content/upload/20169371313.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/morufasirinexavulebowul.pdfIn PDF document text
    • https://ladida.asia/sporlegen/administrator/imagetempfile/89656595231.pdfIn PDF document text
    • http://canyonmeadows.org/userimages/bomuvurebol.pdfIn PDF document text
    • http://mehmetrasimmutlu.com/icerik/file/85108651105.pdfIn PDF document text
    • http://ags-sib.ru/ckfinder/userfiles/files/77509657587.pdfIn PDF document text
    • https://doctornhospital.com/banglanews24/editorsfiles/files/44802819133.pdfIn PDF document text
    • https://maribon.net/app/webroot/files/userfiles/files/giravidigalutujefolubi.pdfIn PDF document text
    • http://savaksangida.com/resimler/files/tomijetigulogusowojuxe.pdfIn PDF document text
    • http://thuonghieutoancau.vn/uploads/files/lelagiz.pdfIn PDF document text
    • http://xn--oy2b19v1mb1yi.com/userfiles/file/72544343483.pdfIn PDF document text
    • https://tramhuonghanoi.vn/upload/files/88603852230.pdfIn PDF document text
    • http://domingo.hu/ckfinder/userfiles/files/65247881131.pdfIn PDF document text
    • https://flexi-cms.com/uploads/file/7101663872.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1612f8f1e81c76---gularudelexi.pdfIn PDF document text
    • https://people11people.gr/uploads/File/sijorojopud.pdfIn PDF document text
    • http://zjhywt.com/images/upload/File/60875119748.pdfIn PDF document text
    • http://abbwingslynnhaven.com/uploads/files/zotedumu.pdfIn PDF document text
    • https://mosconi.net/userfiles/file/gadosimoti.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/54783571849.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16141f2ab2b30d---7182707076.pdfIn PDF document text
    • https://takipcisec.com/calisma2/files/uploads/xikopaxumo.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/jazozowesevevubilu.pdfIn PDF document text
    • http://parvazyab.net/basefile/api203/files/xazeresomilukogojijaje.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_off0000cd32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD32 17564 bytes
SHA-256: 760344dbf10f58659307d263008ca1b3b3370589d786980664c8835dd0dfee65
font_01_sfnt_off0000fa8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8E 11160 bytes
SHA-256: ce0cf9355d612e6b137c9ab97e2c387c091c897f345b6a8645120c7429f3bdfb
font_02_sfnt_off00011493.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11493 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1