Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf7e63eac06a61aa…

MALICIOUS

PDF

84.7 KB Created: 2021-07-01 22:08:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 27cb393fcd1039ebd453d386731b4591 SHA-1: 05ddaff46c7023275f5313e188ced8673794055a SHA-256: bf7e63eac06a61aa741d788422fcd19c87b54e4e266b946032b912c17f17784a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads and disposable hosting. These links likely serve as a distribution mechanism for phishing or malware, aligning with the Spearphishing Attachment technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://remproekt-m.ru/admin/ckfinder/userfiles/files/91690798401.pdf
    • http://sh-ruiyangcpa.com/userfiles/file/2021-6///202162010998868.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/c269fccde4f1790f9cee700a27639437/90715586390.pdf
    • https://codecs.ro/images/file/81533296921.pdf
    • https://maclashoes.it/file/gediginuzinolikusifoli.pdf
    • https://elektrona.cz/files/file/39813735802.pdf
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1607abfe882954---44483724947.pdf
    • http://lawngo.net/fckfiles/39192591125.pdf
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e74e581e79---62085541903.pdf
    • http://drivescuolaguida.it/userfiles/files/50067488009.pdf
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/321bfac7d530894300283729e1a6c003/xogojoda.pdf
    • http://wjvanderheidedienstverlening.nl/uploads/file/gufakowufobogozuvi.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160beaa7c5468e---33809993168.pdf
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aaad119b199---76903481840.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf6a66a3c5---jitujalozinidivoj.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a2e53e043e---58644512686.pdf
    • http://www.cerel.eu/images/wyswig_images/file/tiwowinuguwasavirosavali.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/2a3bn5jbk3icgdb0d3c3j3md95/4680198934.pdf
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/74291735670.pdf
    • https://beatmuellerfoto.ch/userfiles/files/wenoz.pdf
    • http://kgmda.com/upload/files/livomifimepodema.pdf
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/9468rrd7s7vm6ce6bcbli5mnfe/22351734815.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=cubic+in+to+cubic+yd
    • 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_off0000e707.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE707 16792 bytes
font_01_sfnt_off0000ff1e.bin
da618c84470fd113325764f2550010fe82d14bbb2a876e8050b69e6591571dac
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF1E 10140 bytes
font_02_sfnt_off000115e9.bin
a4455a8bdebd7e3cdb4cc21485f21391cd50046666a4ed51f7ca0de686a7da82
pdf-font-stream PDF embedded font (sfnt) at offset 0x115E9 18084 bytes