Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b050e6e02e0e103…

MALICIOUS

PDF

80.2 KB Created: 2021-08-03 22:11:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 512dcdf577c9386ee36e949640e9e6c2 SHA-1: 8a190e42bacc245b240a21742cd96ad0eabf1df7 SHA-256: 8b050e6e02e0e10310ff5d24d444272a005ed6484960e5d1b78676533ef73027
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm for SEO poisoning or malware distribution. The ML classifier strongly flagged this PDF as malicious. The presence of embedded JavaScript suggests an attempt to execute code or redirect the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://synerhu.ru/uplcv?utm_term=nursery+rhymes+mp4+free+download+in+english
    • https://corumosmanlimakina.com/js/ckfinder/userfiles/files/87039523925.pdf
    • https://rewaqousha.net/userfiles/files/punivomiviniruz.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/373ece913c68a8ee3c466b276930b5a7/92956864751.pdf
    • http://aftckwt.com/uploads/file/zuwilavepefigex.pdf
    • https://orangerun.re/photo/files/lavuzodovojesi.pdf
    • http://staractivecollection.com/resimler/site/files/rigudofimetazorex.pdf
    • https://chmelo.hu/sites/default/files/file/12364960743.pdf
    • http://kythuatviet.vn/uploads/userfiles/file/64112758335.pdf
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a6bf1319db3---ferejafi.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/1b1m5v3b4bm52nqm4npi3s9b2q/61723642973.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d6ae643bdbf---vinawap.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef44bbb4e7---83932158997.pdf
    • https://nada70.org/userfiles/file/58651770489.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bb68356fdfa---999324454.pdf
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/7bb42ce33017cc798dc0a5b442301352/tujikukope.pdf
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16090c86157f46---90188905573.pdf
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/17dd2995a18bfe1b1999ab49388b76e5/58436765736.pdf
    • http://curry-box-deluxe.de/userfiles/file/96382682382.pdf
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160982fabb37e3---jovulivutosuxezu.pdf
    • http://vtdsbinhthuan.vn/public/uploads/userfiles/file/zexovesun.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/7aaf2d45326efa2d67a7f5f8547aaf47/78264243358.pdf
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/8f4ecdf62df1ec8b24619b99725932ee/puvoketeviwawur.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16095cea0e11a0---zigujubowologalafo.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_off0000d27b.bin
bc4de7e9720f7ea5c81cd3a7295eca86b974f208c3c0da784bad6fd2b9a4009c
pdf-font-stream PDF embedded font (sfnt) at offset 0xD27B 11200 bytes
font_01_sfnt_off0000ec6b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC6B 16792 bytes
font_02_sfnt_off0001047d.bin
c98193b31a2bba5f9256e35b980c3278e4e24a55c01addbc456578a2d5acaca3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1047D 17572 bytes