Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bf4d4e9f6a9649e…

MALICIOUS

PDF

87.4 KB Created: 2021-07-14 03:49:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f7c1407b6f9555d41aad26af68e74fb1 SHA-1: b8984a6f9dff0dd874d3a6b5c71159a819b8fc90 SHA-256: 4bf4d4e9f6a9649e430a6e968129dcbb43a92c0ea4e6e26a9b17399fa7c1c2d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware through these links. The document body is unreadable binary data, providing no direct user-facing content.

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://ithaca1966.com/clients/8/85/85e9e0a76fddb83d7689cebc6ab07fae/File/basirizufafivaluguwowemom.pdf
    • https://vettercycles.ch/userfiles/files/minuxedago.pdf
    • http://share-world.tw/userfiles/file/vekuxubiwotubosimifadox.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1608ecde263860---11725647033.pdf
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607a81d5d4f68---revigi.pdf
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/08e5c35e74df4ee37674148434e7ebbc/velowawosuzezamilad.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606f75fed95c8---kuxedukafifalowuwazanibe.pdf
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/212711674560e5311bb34af.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c950a354f0---wanexorawawaro.pdf
    • http://sacoorhealth.pt/site/upload/file/pokuvonuwed.pdf
    • https://chulintemple.org/CKEdit/upload/files/pilaxewulipixeturibavuz.pdf
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/80a35b75d5bbc5d6cd312ff39f188659/vawizavuwebizemoz.pdf
    • http://autosoftware.company/autoresponders_images/files/26760286730.pdf
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607a93500dac6---nokul.pdf
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160912f7a6aec1---seporatewage.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba258895d83---5773651502.pdf
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/a08c84f506ef577f51ae0fe1ef49a624/wezelanufilufo.pdf
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160920b935b7e0---rubowoxo.pdf
    • http://tubietelbar.hu/uploadfile/3490111992.pdf
    • http://sllight.ru/design/img/upload/file/luramokedusaxibemutater.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a81f40545---pezikokusa.pdf
    • http://aaz.sk/editor_uploads/files/diduv.pdf
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/489d4c90763d92c2e8427db7d2ed1b4c/kisevedowuvox.pdf
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/d43da1f0705ad6292d34b2b80de0cf2a/lexutebudatesipakegixepof.pdf
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607b70ce169e8---61592633459.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=tendons+and+ligaments+are+made+of
    • 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_off0000f5ed.bin
fde46d7c3246a47789ed9f822fe9bdc84694da7fc7ac89c3c7bbc26bf4338be6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5ED 16268 bytes
font_01_sfnt_off00011fce.bin
a16386444600f14029d8f09fdc4b17d02adf25effb35a605b2882e02da6ba5ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FCE 10660 bytes
font_02_sfnt_off00013801.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13801 16792 bytes