Malicious PDF — malware analysis report

Static analysis result for SHA-256 dacf5640fe64733d…

MALICIOUS

PDF

69.1 KB Created: 2021-04-08 12:06:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 259a3791af20642983169cf02fe0c7c1 SHA-1: 391bb2b28b16f12d3ab01349c191c82e9416b76f SHA-256: dacf5640fe64733da0f16f2a46db7ac04d32c9443d14eac8065faa5d718e9f92
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document contains numerous links to distinct, potentially disposable hosts, suggesting a link farm used for malicious redirection. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to direct users to malicious websites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://vectorcorp.net/sites/default/files/webform/resume/30106672217.pdf In PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/74543186253.pdfIn PDF document text
    • https://aboss.by/sites/default/files/webform/12404161593.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/bunovodedodasu.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/27999686052.pdfIn PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/30232074114.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/keborezuvefubivuw.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/xojisipet.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/31626011693.pdfIn PDF document text
    • http://www.birdlifebotswana.org.bw/sites/default/files/webform/sightings-sketches/beporu.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/69309865186.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/72246142748.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/taxebuvokorutupimapo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=basics+of+computer+and+applications+pdf+for+rrb+jePDF link annotation
    • https://lib.asu.edu/system/files/webform/simadovi.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/dovekilubexuvizufak.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/26909318775.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d091.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD091 5564 bytes
SHA-256: d80bc5d360a8e678a8cebcea031301351ad4c4c7f8c9ac21044c54baa9d094d2
font_01_sfnt_off0000e365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE365 10504 bytes
SHA-256: fd14b4c8621dc55dc80fc1429520e8959060232e1fb4bf2b6fad267d1e3248aa