Malicious PDF — malware analysis report

Static analysis result for SHA-256 d94fb5303fcc9996…

MALICIOUS

PDF

70.8 KB Created: 2021-09-25 02:32:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 334a4746e15ceb4b7d2dff2e0b4edc7f SHA-1: 06e4f15f2a712ef4bbc65883be59e8a123f392e3 SHA-256: d94fb5303fcc9996c578355651b4305794d519d44f40e5d817e6e5655851bd2d
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm and by a machine learning classifier as malicious. It contains numerous embedded URLs pointing to domains that are either compromised or appear to be disposable hosting. The ClamAV detection further confirms its malicious nature, identifying it as Pdf.Phishing.Trojan. The primary attack pattern involves luring users to click on these links, which likely lead to phishing pages or further malware downloads.

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 http://xn--4k0b43gkwo4gn.com/upload/editor/file/24714285000.pdf In PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/24525063303.pdfIn PDF document text
    • https://bhandarisurgical.com/ckfinder/userfiles/files/96145330370.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/0b4ba737ef6484277ec103235993344b/33546463038.pdfIn PDF document text
    • https://aldwalia.com/userfiles/files/13513443118.pdfIn PDF document text
    • http://shopabrang.com/images/files/galugokipe.pdfIn PDF document text
    • http://cbestdesign.com/ckfinder/images_store/files/xalibemulido.pdfIn PDF document text
    • http://klsele.com/userfiles/file/1632203978.pdfIn PDF document text
    • http://kamnitikamini.si/upload/files/dufesesosiximurajefak.pdfIn PDF document text
    • https://vico-domrep.com/ckfinder/userfiles/files/fetusidenetusomoxu.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161459a891df31---sikefife.pdfIn PDF document text
    • http://edbiji.com/uploads/files/20210924110449_315275.pdfIn PDF document text
    • http://volareinmongolfiera.it/userfiles/files/disujakitufigur.pdfIn PDF document text
    • http://proleague.dk/userfiles/file/401395579.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161427f75a6057---zikojidujope.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/3904119573.pdfIn PDF document text
    • http://csim.jp/ckeditor/uploads/files/debozejor.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/161381b2e98da9---67888864411.pdfIn PDF document text
    • http://bourgogne.annuaire-regional.com/ckfinder/userfiles/files/sufokalo.pdfIn PDF document text
    • https://spotiverify.com/ci/userfiles/files/bareve.pdfIn PDF document text
    • http://koryosushi.com/uploads/files/89938479985.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=english+phrasal+verbs+in+use+advanced+book+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000af95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF95 11180 bytes
SHA-256: 178274786fd76160b1948f6699cb05bb38785a73c4b10bee8f8ead3686961bbb
font_01_sfnt_off0000c935.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC935 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e147.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE147 17368 bytes
SHA-256: 74f8e5f7b4ff612af1731c7bb5775f2709963369243357ba276f5fb12b7009f7