Malicious PDF — malware analysis report

Static analysis result for SHA-256 51706bbb90caf800…

MALICIOUS

PDF

140.8 KB Created: 2021-09-13 14:01:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9baaea245b83e429f93315f3b7705202 SHA-1: 7f6d9b5077a13a17986e25b8b1a2faa3b030e5aa SHA-256: 51706bbb90caf800303698bfb07742e71738b0a31924eb2647bf960d02dedd1f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple domains, some of which are hosted on compromised WordPress sites, suggesting an attempt to distribute further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution lure, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/kawiwazeguviw.pdf
    • http://spiregene.com/image/files/20210913_024522.pdf
    • http://haciogullari.com/depo/sayfaresim/file/44513944295.pdf
    • https://dennismaloney.ca/upload/editor/file/87924454751.pdf
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/lotubuzamazefewosal.pdf
    • https://vanvoorst.info/uploaded/file/fumasada.pdf
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe3c10ab56---pakofopomimi.pdf
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/14b0eaaa31e13f5cc77652f41162a9f2/gavugulinaxaj.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/161302126ad98b---bapevajadekanoku.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613971c6d7821---91578132979.pdf
    • https://www.verimevzabavu.cz/ckfinder/userfiles/files/17748924235.pdf
    • http://brixtontaxi.com/survey/userfiles/files/32180089854.pdf
    • https://orig-shop-gsm.ro/ckfinder/userfiles/files/zalawo.pdf
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/49796370392.pdf
    • http://kavernoklub.com/campannas/file/mujuwe.pdf
    • http://cuoredicane.it/userfiles/files/lerifisesexobexuredakuz.pdf
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/ec5aa2ecb8d87b46d159f2de6f04a9b0/neragane.pdf
    • https://mamo-tato.ro/userfiles/file/44566348808.pdf
    • https://salondumariagededijon.com/userfiles/file/23314205316.pdf
    • http://farmaciafoglia.eu/userfiles/files/bitowem.pdf
    • http://dreiseengrundschule.de/files/xapuvaxigegowur.pdf
    • http://sportingclubalbinia.eu/userfiles/files/pilonokolupuzijukomuxumu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=construction+simulator+2015+mod+apk
    • 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_off0001bfbc.bin
afe8ab111654029ab542bcdf3b6a1bf5f56c594a5d2670bfddbe9f2fecbcf85b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1BFBC 11192 bytes
font_01_sfnt_off0001da17.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1DA17 16792 bytes
font_02_sfnt_off0001f229.bin
57e4416446cb7c5c0772dd12f3af4458cf2eca2099790a9059c11755cd63e817
pdf-font-stream PDF embedded font (sfnt) at offset 0x1F229 19424 bytes