Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3cae6a602691f50…

MALICIOUS

PDF

100.6 KB Created: 2021-07-03 08:47:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 67bd0d64da90c4947238139beae39a0b SHA-1: 2f87af108a5614c523a3503a735b2d042e7c0abe SHA-256: c3cae6a602691f50e7277fd3a4ef6968a7b3d08daff03e5ceb43ffab34b7a0ff
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous distinct hosts, many of which are identified as compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9938

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://softwarefactory.nl/images/file/zolikavow.pdf
    • https://soechi.net/userfiles/file/76057312487.pdf
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/m5dgutjivgc04vnrv5e3llsln7/zasevavusawokegomurovuben.pdf
    • http://ahsaipu.com/v15/Upload/file/2021511831257479.pdf
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/5f16a86475cd04a1d13aed27b80530fd/tenozunafikod.pdf
    • http://vanhoadautu.vn/static/uploads/editor/files/xakukuwexoda.pdf
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf04d66d15a---tusamugewapapa.pdf
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acfead53e0f---fatiletesigadajupijasoz.pdf
    • https://grupo-kayros.com/userfiles/file/4210440411.pdf
    • http://botosani.ro/img/uploads/file/49459645328.pdf
    • http://eros-arena.de/eros/userfiles/file/59513374180.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4fef853500---silizenirajaw.pdf
    • https://landbondcorten.com/attachment/file/36f41b3471627db7dcb807b49db81729.pdf
    • https://aquarell.ro/userfiles/file/7821951521.pdf
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160bd422a72d4c---60991537385.pdf
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/3001b7d1ffc2e9011db231e6da84d4df/sedosukarafatagexo.pdf
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160948eb9000ae---milazusowejidugik.pdf
    • http://bioscipublisher.com/files/upfiles/file/26289643938.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/t0c7d4ql3evde6oh3f6o1571ch/52438774144.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec223c2b6d---55330829495.pdf
    • https://anukulagrotech.com/userfiles/file/74871594994.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d31c49c38a6---29984745277.pdf
    • http://rc-modeller.se/images/file///rokufexejulevokubinos.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=thomas+calculus+answers+13th
    • 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_off0001209a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1209A 16792 bytes
font_01_sfnt_off000138ac.bin
d00f00cb6db2d9affed7e0831e252bcbced19a1b00626562a55bb7673962622a
pdf-font-stream PDF embedded font (sfnt) at offset 0x138AC 19128 bytes
font_02_sfnt_off00016aeb.bin
85c85ee2dc37a0ccdb25e335def639d69f746d3c61d332837c3893f1de13cb3d
pdf-font-stream PDF embedded font (sfnt) at offset 0x16AEB 10776 bytes