Malicious PDF — malware analysis report

Static analysis result for SHA-256 836646ebed48c2f3…

MALICIOUS

PDF

87.1 KB Created: 2021-07-04 11:00:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d0a6b52b419a5d8f70da74f8e42be99d SHA-1: eb59ec4953b00c24ac8ef82112ac8c8ef45e88bf SHA-256: 836646ebed48c2f3e0ad1060a15b93033c221999d924db3be2ada05e70cd27cd
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites and disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 https://autotrasportifenoggio.it/file/mizip.pdf
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dec8e028087---titewimuledopijaruv.pdf
    • https://banktapeunadana.com/tapeunadana/bank2/admin/userfiles/file/19830787218.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba088825a67---fifubudulo.pdf
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/16077637e740e1---83717326500.pdf
    • http://nano-vip.com/ckfinder/userfiles/files/8089717012.pdf
    • https://digireg.cz/upload/munavaxakejudofizewij.pdf
    • https://eatorhours.org/e-bussiness/fckimages/file/32036063764.pdf
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1a552c164c---91312489212.pdf
    • http://olgapolyakova.com/files/files/40972811768.pdf
    • http://transinfosoft.com/userfiles/file/puzisabivok.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f33ca6063---rovagagulotujusixat.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607db55cbdcaa---safunovuzeduzuxafixinuxu.pdf
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160724abe339b4---28993130420.pdf
    • https://sheenabusesandcoaches.com/userfiles/file/pijofetafe.pdf
    • https://inncredel.com/uploads/kowekerunorerorebutu.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099b0b7b86ac---48059915611.pdf
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/c462829a9b5b61752fdaee3c623ceefa/kuwajaki.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/4qfngjus04m4qbbb19m62pnq17/mosafakabilufesikobumu.pdf
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/c42e3b978e3c76a10ede79b555969b45/lizonubuxefo.pdf
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/d2a7f7a1fcfecd5d1bad0a09493b6169/81806216041.pdf
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/2520bd4454bb29f3adb14b2bb427df53/wovogujuvukivapi.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=strong+adjective+words
    • 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_off0000f16f.bin
ab8b45bb10cf99a524198694bddc26df9b93bc63c6b17d013aa966c12bcb30c1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF16F 17732 bytes
font_01_sfnt_off00011f85.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F85 16792 bytes
font_02_sfnt_off0001379c.bin
4e942032764f6b8f4d9eb2009564336dc0d64aa0194da58e36bcb49d5e8c035b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1379C 10856 bytes