Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f33237b55990606…

MALICIOUS

PDF

83.0 KB Created: 2021-09-12 14:17:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a8b1a547914e3d65918577dd7410ed97 SHA-1: 8dc52427f91d22c38a8c135364647b15947c1368 SHA-256: 4f33237b55990606ea138324aaa6a1e80f7d36718240c50ae3f49fc4a959731c
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected by ClamAV as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. The ML classifier also strongly flagged this PDF as malicious. While no executable scripts were extracted, the structure and URL patterns suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://associatedreclaimed.com/userfiles/files/86113261389.pdf
    • https://cape-electronics.com/media/file/nozivekaw.pdf
    • https://webvitamin.vn/app/webroot/uploads/files/9493628733.pdf
    • https://martan.es/cenavarra_userfiles/files/kuwitele.pdf
    • http://showpalmedical.com/userfiles/vijinafami.pdf
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613164e6e3bd9---xonarokile.pdf
    • http://www.hgekc.com/media/userfiles/file/17999024945.pdf
    • http://agriturismolataggiasca.eu/userfiles/files/70731149227.pdf
    • http://getem.eu/files/file/sovuvagup.pdf
    • https://epagneuls-bretons.fr/caningest/images/file/1552841469.pdf
    • http://plaschke-partner.com/uploaded/file/jisugez.pdf
    • http://gallery4walls.com/upload/editer/file/22140142831.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131c943e406e---buwevopasemuvapimut.pdf
    • http://3e3i.com/UserFiles/file///puradaxujoxotodevaner.pdf
    • http://avon-bratislava.com/files/files/pibinilofusamobuzewuse.pdf
    • http://larben.cz/media/images/upload/file/nalimu.pdf
    • https://digireg.cz/upload/88437626110.pdf
    • http://consol.hu/images/uploadedimages/file/3643496505.pdf
    • https://socardan.com/userfiles/files/menizim.pdf
    • http://jlsxjy.com/right/UploadFile/file///2021090715522373499.pdf
    • https://hainutedecopii.eu/ckfinder/userfiles/files/64173904094.pdf
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135bb06458be---40848880061.pdf
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137d51f036f3---vafewapadopiwavexoj.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=mod+apps+market
    • 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_off0000e194.bin
c5c38418807a33cbcb8cc486dbd972c4117cc7981c202e0ded692d4c4957e28b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE194 17748 bytes
font_01_sfnt_off00010ee0.bin
596dbf7ed7e9a97dd95ef3f2f0c2a9b08ff355e727d58b012d9681aede4f1f18
pdf-font-stream PDF embedded font (sfnt) at offset 0x10EE0 10396 bytes
font_02_sfnt_off00012672.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12672 16792 bytes