Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5b50cbca306f4dd…

MALICIOUS

PDF

93.9 KB Created: 2021-07-30 09:31:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 811acabdaa5fcff57b96a837a5b60f78 SHA-1: 65c524ea2883bbe415ae4ea000ecc35a9b5da1e8 SHA-256: d5b50cbca306f4ddfa6a597d51fe6910636794dc9468223ae3686f64e40938a9
156 Risk Score

Malware Insights

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

The PDF document contains a large number of links, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of a link farm on disposable hosting and compromised WordPress sites suggests an attempt to obscure the final destination and leverage vulnerable infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/fomosuzigalapewubovituw.pdf
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/bde4e8dddb7d1601da34f9e00c2d9fe2/47009729052.pdf
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/f08f8741e3eb9d4917207d60d73bf882/wujek.pdf
    • http://group-anons.ru/userfiles/files/rirukipufeze.pdf
    • https://scavilecis.it/userfiles/file/99342484176.pdf
    • http://domingo.hu/ckfinder/userfiles/files/95649732886.pdf
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/0991ce112aa9bc2c89076c1a99870d9d/winibib.pdf
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/etb02nbsuu2ro6nr4p1l34a3p9/wazapuwefapazadix.pdf
    • http://saovietgroup.com/upload/FCK/file/89336283004.pdf
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608654a448910---32538291176.pdf
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160b36536592f6---52134995997.pdf
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbe58265ed5---97702308777.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160f49b67e8e1f---dufugipiwanilumeve.pdf
    • http://kibbkw.com/uploads/files/65351233281.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083f0e630503---xowakotiditomusise.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/712b86ffe12373e290febe47f5f01ea9/2285034865.pdf
    • http://kapelski.pl/userfiles/file/nimigosinigatu.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16072a22247b83---nemenajavexebezulipaluz.pdf
    • https://majorsagilekvaros.hu/uploads/file/30970096373.pdf
    • http://rlangkhan.com/upload/userfiles/files/26835718248.pdf
    • https://dewalt-naradi.cz/media/upload/editor/file/welamef.pdf
    • http://indel.sk/userfiles/file/wogijabaf.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609d395b14242---vesoneditiwo.pdf
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/rajsdtis6vnqbc3ghi1obli60u/jagupenibabiviloji.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=focusrite+scarlett+solo+3rd+gen+installation
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f035.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF035 16792 bytes
font_01_sfnt_off00010846.bin
fd494554c7a7a2c4488382a78096c535ff133766c7221992be4f6a58596b2467
pdf-font-stream PDF embedded font (sfnt) at offset 0x10846 16164 bytes
font_02_sfnt_off00011dbd.bin
0caaa59318e49c13fcd758987fe0f105ad68c7fccc00fbf7232274da18782372
pdf-font-stream PDF embedded font (sfnt) at offset 0x11DBD 10792 bytes
font_03_sfnt_off00013682.bin
25603c05ac26cc23511e9a5880ee77dddbce127bf1081f78f004de5926dec09d
pdf-font-stream PDF embedded font (sfnt) at offset 0x13682 18544 bytes