Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f4d8a5993d7e3aa…

MALICIOUS

PDF

71.5 KB Created: 2021-10-02 12:49:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a38859f9fa268758f8bba560b065d7a SHA-1: d2ff385af331b22797d67868d2b2a1f03e331cde SHA-256: 4f4d8a5993d7e3aa3e6561ab768f330987fad341c3b760715c0c806abc854e68
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it is a link farm and a callback phishing lure, consistent with a scam. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were extracted, the presence of embedded URLs and the nature of the heuristics point towards a phishing or scamming operation, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://ketchas.ru/uplcv?utm_term=hearse+funeral+car+for+sale
    • http://satakantaresort.com/user_img/files/21905184485.pdf
    • http://softtox.com/new/userfiles/file/pixolosazavo.pdf
    • http://nationalherbo.com/userfiles/file/57326869347.pdf
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140260d9eae5---6398036148.pdf
    • https://bawaniint.com/ckfinder/userfiles/files/64675783110.pdf
    • http://www.syrahresources.com.au/application/third_party/ckfinder/userfiles/files/dovatorepex.pdf
    • http://devison-matras.com/upload/file/72251847310.pdf
    • http://unseenadventure.com/userfiles/file/50739600426.pdf
    • https://bimetoor.com/basefile/bimetoorir/files/weniluxobubabasepetexefeg.pdf
    • http://vssteel1999.com/ckeditor/userfiles/files/nikanitukowu.pdf
    • http://puebloexec.com/userfiles/file/72442901053.pdf
    • https://adikkeempat.com/contents/files/tikudanetulivixajugasebav.pdf
    • http://limeitec.com/upfiles/editor/files/1771273893.pdf
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/pilis.pdf
    • https://plagij.at/ckfinder/userfiles/files/93689713545.pdf
    • https://dnmpaint.com/sdcc/images/file/josumevupijajosevepo.pdf
    • https://jimsdelibrookhaven.com/demo/jimsdeli/admin/userfilesfile/66384817011.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614af1c91a77d---bisosunoro.pdf
    • https://asp2.aiwangyun.com/ckfinder/userfiles/files/48539418543.pdf
    • http://logistra.fr/ressource/site-image/files/93910286570.pdf
    • https://cafesca.info/ckfinder/userfiles/files/tebojobezofabigejukolabi.pdf
    • https://aordonez.com/images/contenidos/files/jopusebepepezir.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ecd0db3282---wizimudirog.pdf
    • http://oticonshop.com/ckfinder/userfiles/files/tobanabuvapazemikizugi.pdf
    • 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_off0000b59d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB59D 16792 bytes
font_01_sfnt_off0000cdaf.bin
02067713cc7cb85918e092c59a320fa2a23beec6bc09fd97a2499dc571f66246
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDAF 16864 bytes
font_02_sfnt_off0000f8f6.bin
1d7efc4055398dc77d21b8026d5d856727ee587bb69ba5b5e1fc3726dc8fc0dc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F6 10228 bytes