Malicious PDF — malware analysis report

Static analysis result for SHA-256 18fa2f5e601aa6e3…

MALICIOUS

PDF

73.8 KB Created: 2021-09-27 03:35:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 51077100173f66f3238cf2f2ef091105 SHA-1: eeea7f5e1b4500777b4f1f25f5d74270f3b4e66e SHA-256: 18fa2f5e601aa6e339c4195e6fbb933a21c98604ea12f5245eee2658d36f9afa
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites. Heuristics indicate a 'link farm' pattern, suggesting the primary purpose is to redirect users to external, potentially malicious content. The ML classifier and ClamAV detection strongly support a malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150579c04520---20360445660.pdf
    • http://pes.edu.mn/ckfinder/userfiles/files/liziwufi.pdf
    • http://tutek.eu/userfiles/file/xazuxejofavatapu.pdf
    • https://tessuno.com/upload/files/6150e48db1e5b.pdf
    • https://suacuacuontoanphat.com/upload/files/kidujotitoxolalexes.pdf
    • http://daegyung.kr/userfiles/file/20210903093050.pdf
    • http://emeat.ru/var/files/furekiwonovewasa.pdf
    • http://acril.ru/ufiles/files/poginatijilupon.pdf
    • http://ilovestory.com/upload/file/90571430275.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1614acaae43651---99618361414.pdf
    • http://botosani.ro/img/uploads/file/vajuzitimuvifigofexal.pdf
    • http://artio.pl/files/files/51751253535.pdf
    • https://monographie.com/ckfinder/userfiles/files/rodevorutatijesovo.pdf
    • http://delfosventures.com/userfiles/files/96775006569.pdf
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1614d7f8ba28d2---wabobezeluxazilozekosiwa.pdf
    • http://tecresconsolidamentorestauro.it/fck_data/file/50840805793.pdf
    • https://homestayhoian.thamtuddt.com/uploads/image/files/24064010970.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/16150ead159795---suketajaxorumebise.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/coivofvj1i6s9p9snsmss3uqkt/sajenulimamopita.pdf
    • http://cerescommoditiesltd.com/Images_upload/files/ranug.pdf
    • https://www.vignolaweb.it/ckfinder/userfiles/files/beboj.pdf
    • http://harchovyk.com/userfiles/file/konuxiwijakapetufobaxo.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354feadaa00---38727965318.pdf
    • http://randoquad72.fr/userfiles/file/zekewisaximore.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=barron+ielts+3rd+edition+audio+free+download
    • 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_off0000b590.bin
2799b79f5c1558388684e867c1f7c8f5bec0102713735aa67f14ee153bb05491
pdf-font-stream PDF embedded font (sfnt) at offset 0xB590 19972 bytes
font_01_sfnt_off0000e7bb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7BB 16792 bytes
font_02_sfnt_off0000ffd2.bin
721bbc90ba97ab3d4812b75b5de85e4ea7bc75df083a24c4a055029d6da56397
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD2 10756 bytes