Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c032254b0bc98ff…

MALICIOUS

PDF

83.1 KB Created: 2021-08-17 13:28:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2af1e2290ba0c5f72cf884fadb9d6011 SHA-1: 3fd7546388e18aae197a510332e350d11394ecee SHA-256: 4c032254b0bc98ffa7c02b36e44f0aba0bd36c5cb0d9fe1f7432ccd5d9d8733b
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file exhibits characteristics of a malicious link farm, with numerous embedded URLs pointing to potentially compromised websites. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics suggests an attempt to distribute malicious content or phish users by directing them to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://cructi.ru/uplcv?utm_term=how+to+improve+listening+skills+in+preschoolers
    • http://zulaikhatextile.com/userfiles/files/20247515084.pdf
    • http://sjar-tech.com/uploadfile/file///2021052212211289.pdf
    • http://openendrep.com/userfiles/files/mawul.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/a94451f2106dd45d734d04bec4cbefc3/pupuvur.pdf
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/9fc3ea1a1373857ca243cdce9e35a2fe/milulikejigijidi.pdf
    • https://maychieuvinh.vn/upload/files/nowanofutofejalas.pdf
    • http://netinflux.net/userfiles/file/41518221660.pdf
    • http://arcos-eff.it/userfiles/files/15406200877.pdf
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a61fdaa364e---wikimag.pdf
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b80ac57f41---borirubekusekasoxibozug.pdf
    • https://christianklein.eu/Quansis/ckfinder/userfiles/files/67324041573.pdf
    • https://npkfertilizerproduction.com/d/files/8806212549.pdf
    • http://farmaciafici.com/userfiles/files/sajafapevaxu.pdf
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/7305c41f1b3339ce06c1d2d11248e5c4/pariwobadiwusuwebidege.pdf
    • http://iccjsc.com/images/uploads/files/dokofuzifelupowasesop.pdf
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/h8d4n96t0eq7jf3g6o34t49tmh/vezibomedafazivowolakalu.pdf
    • http://summitremodelinginc.com/userfiles/files/raxulijo.pdf
    • https://www.hasmow.com.au/application/third_party/ckfinder/userfiles/files/70318360383.pdf
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/c4ddae84c25a1c162256498492a72674/10224079983.pdf
    • https://kaptenhoki.com/contents//files/94084915396.pdf
    • https://activepymes.com/pub/file/xutugexepa.pdf
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/2d2d66af077b32516a50a5ef1f27bdb9/xeritubugekosidotozobapa.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/fkaj6u1hm2hbp122p14hu31487/vukajememagivig.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_off0000e05e.bin
83d6a29ed5fc66fc826a70285687e15e69420d636a9f22acc006d314c4f4be64
pdf-font-stream PDF embedded font (sfnt) at offset 0xE05E 10892 bytes
font_01_sfnt_off0000f960.bin
a7c4c0fb1a5f7047c56d655f6bc4aa9a75891e746f2ad70c0f5a003894bb99c5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF960 16864 bytes
font_02_sfnt_off00012525.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12525 16792 bytes