Malicious PDF — malware analysis report

Static analysis result for SHA-256 41c729e8db5fc118…

MALICIOUS

PDF

86.7 KB Created: 2021-07-17 15:56:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 22117919fc7f5b9cb22f4cdbf722e6e3 SHA-1: cc080652055fe428e09bc295dfbf19ea4d112566 SHA-256: 41c729e8db5fc118cddf261aaa7a03dd6856b97fc8254ae4f17f302956f0921f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as 'Pdf.Phishing.Trojan'. The document contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting, suggesting a phishing or malicious redirection scheme. The presence of a link farm indicates an attempt to lure users to external, potentially harmful, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://xn----8sbxab3abskk3a2j.xn--p1ai/media/file/jiwesobizolavasavarofur.pdf
    • http://interel-rus.ru/test/sites/default/files/file/xasexizodesisugowilubo.pdf
    • http://shreyaghoshal.com/konadnew/userfiles/file/zofisobi.pdf
    • https://apz-arte.com/ckfinder/userfiles/files/mosotovevulijebozaguvokax.pdf
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609a6c91f14fc---90399047245.pdf
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc4ca1d86ab---68802412741.pdf
    • https://dehayemek.net/upload/ckfinder/files/29198740959.pdf
    • https://kozhikodedeaf.org/admin/my_files/file/bawosona.pdf
    • http://cathyknightwaite.com/ckfinder/userfiles/files/95446840890.pdf
    • http://hublihorse.com/uploads/userfiles/files/kupepunonegam.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4fcd339f42---13171951875.pdf
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a541c291192---mawoko.pdf
    • http://mea-travel.pl/userfiles/file/paxufibetivix.pdf
    • http://fructusartis.com/i/File/93381182711.pdf
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/b3a9c7ef36e7f9d5377c5916e683eb6d/55582406826.pdf
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/rvc996i3fak3c8vnts7guuispr/36025510630.pdf
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607abe2960fe7---regovutoxuragolegu.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fe6477e2a9---51108888531.pdf
    • http://sacoorhealth.pt/site/upload/file/38400967124.pdf
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/938be58e37e5346be8e9dda623fe019f/50600732498.pdf
    • http://kasaitogo.com/uploads/files/bumuputopogevurijikij.pdf
    • http://otvorene-srdce.sk/userfiles/file/ferowojigigarufotized.pdf
    • http://jaatkinson.com/userimages/netuvuxufovewusadi.pdf
    • http://cnkls.com/userfiles/file/1623666302.pdf
    • https://flardochform.se/userfiles/file/mesefakisul.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=sole+of+foot+sore+after+running
    • 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_off0000f1fe.bin
608be8cf11540f778581db2496b22fac65a719c3b1615dbf04b3031fec724228
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FE 16628 bytes
font_01_sfnt_off00011d3e.bin
35843206e352aa20fb6cd0905c22736d02cb83b6474f4e2078c543e400b4d49b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D3E 10564 bytes
font_02_sfnt_off00013579.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13579 16792 bytes