Malicious PDF — malware analysis report

Static analysis result for SHA-256 b37fecc6cba1105c…

MALICIOUS

PDF

89.4 KB Created: 2021-06-25 22:31:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7d12b7bdf2f057029d4fb36f1fabe7b0 SHA-1: ddc6c92be83cbbac717d770f81552c10e2e6bd4b SHA-256: b37fecc6cba1105c7d1f5f681e6a1913c42c3bf3fae2c95f4c84207214880791
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of link farms designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristic specifically highlights the use of compromised WordPress upload storage.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://ketchas.ru/uplcv?utm_term=the+upside+down+show
    • http://studiobardinisrl.com/userfiles/files/56026958611.pdf
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/kipefugunopukibulexowox.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/miaja7bi7j5e11phif9p26kh94/46922827457.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082adeaae14f---xijerojesujoratederuf.pdf
    • https://pacie.vn/web/uploads/files/2520578312.pdf
    • http://www.deopendeur.org/imgUser/file/67846679754.pdf
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/lebr9dqkovhcjf810g7q14d206/2137768942.pdf
    • http://www.urbanwaterways.info/files/13446321519.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160b23737776c3---48979786499.pdf
    • https://menuiserie-sainte-anne.fr/userfiles/file/togopamigedutuxugusebe.pdf
    • https://argumentua.com/i/file/60736459072.pdf
    • https://ph2020.org/FCKeditor/file/82140291730.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/pjo16vc87rq1to6lkdhbu8ao1v/rejozupizarumokamuwepat.pdf
    • http://ediljolli.com/userfiles/files/ramuxevoxifefipavof.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/ce81881fd77907c91942916639975ed4/kibudetikezeb.pdf
    • http://kirakuramenandsushi.com/uploads/files/jaxewufuwoja.pdf
    • https://binarbaidservices.com/public_html/userfiles/file/gavofodevibozisunemag.pdf
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/832d7e3dfdc53cc1f4d05684c2a566a0/liwijotidodofimudanaj.pdf
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/4948607bff29a8dfe88dffe8b3b4ae21/loropog.pdf
    • https://ovth.ch/userfiles/files/sagonobumido.pdf
    • http://amazingindiaphotos.com/amazingindiaphotos//upload/fckimage/file/vanevuloropujufi.pdf
    • https://www.mds-horizons.com/upload/files/37680345843.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7a44dc4ac4---gilozopin.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086919c9a149---gubitubigufafi.pdf
    • http://nhs1980alumni.com/clients/878257/File/50167975408.pdf
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160964b0a2a31e---98589972314.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_off0000f886.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF886 16792 bytes
font_01_sfnt_off0001109d.bin
0d343eb409f698a322cffdb9fc266645208c4323c7a7f93de2ffa46770406e9e
pdf-font-stream PDF embedded font (sfnt) at offset 0x1109D 10232 bytes
font_02_sfnt_off0001278c.bin
b5cbecc6ab52e07e17768836b20eb4b7c7f47abbda9b4e42b9490988ae972757
pdf-font-stream PDF embedded font (sfnt) at offset 0x1278C 18472 bytes