Malicious PDF — malware analysis report

Static analysis result for SHA-256 177692358c57bab0…

MALICIOUS

PDF

80.1 KB Created: 2021-07-02 11:20:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 81891870f73a668809a461bd8b02d54d SHA-1: a79fb8cce07b50197d532e0cbe0803d68fd30a1e SHA-256: 177692358c57bab033772cc4b7e2272490df16686100c48648b023ee4c206ed6
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to compromised WordPress upload storage and other potentially malicious sites. The presence of numerous unknown URLs suggests an attempt to distribute further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160859eb23449e---2485224009.pdf In PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/0040f9a0f9bec836c2d6e3c1121800de/73332441020.pdfIn PDF document text
    • http://cunningham-reunion.com/clients/7/73/7399477c88ef979e1ad3ac38e42cffcc/File/66537083749.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9d51c29ff---65269514105.pdfIn PDF document text
    • http://bukvoznaika.ru/ckfinder/userfiles/files/wolanenawebexe.pdfIn PDF document text
    • http://k-souz.com/userfiles/file/tisumajazupizibi.pdfIn PDF document text
    • http://sahamit.net/userfiles/file/xotelo.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/8374bdfbdc4080046f17e91762650383/9248091594.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/c6779d9b86bf51fcc4c560f1b0430db4/fivoro.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/dd5b2b2fd11999d59bf5fd5fef6650bd/davijefezevujuzamomi.pdfIn PDF document text
    • http://nw-line.ru/generic/uploaded/13058099148.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607d65c469762---talofulorusetabivipifiv.pdfIn PDF document text
    • https://peptidturkiye.com/ckfinder/userfiles/files/mavunenumipasedipigat.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/74540476481.pdfIn PDF document text
    • https://ndmoyun.com/calisma2/files/uploads/lesiz.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/ab959a63e5f41de8ff48763728c81838/giwosibuwubanewifuduwozi.pdfIn PDF document text
    • https://digireg.es/upload/79883148788.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c031b2400f1---59798732669.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/16073002f93468---45938790336.pdfIn PDF document text
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/9c02757820ca514fe953dfbc75a096e8/82540884754.pdfIn PDF document text
    • http://www.klimavill.com//data/editorfile/60906292754.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/v2np5k56sg7an446cs88apstpl/51740238155.pdfIn PDF document text
    • http://galluccifaibano.com/userfiles/file/lepegubudogixit.pdfIn PDF document text
    • http://sheeld.org/clients/d/d0/d021426cee8527c21a172be12ef3d645/File/fonuzemifujisetoxa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=give+an+example+of+eachPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d351.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD351 10588 bytes
SHA-256: 76fa62a6a0babd8971fcc8b4ebce25ddbc19e987b528386594c47f4c1239f1a1
font_01_sfnt_off0000eb44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB44 18608 bytes
SHA-256: 71523d205ef8fb2327f72c903ce22e2430bc6292fd05ffff5a0ec8c08644ccb7
font_02_sfnt_off00011b10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1