Malicious PDF — malware analysis report

Static analysis result for SHA-256 f19e531c356e66e3…

MALICIOUS

PDF

80.9 KB Created: 2021-09-05 02:29:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f80bf4d089b57337784e13fae07f2768 SHA-1: af2e002d97c2fa4d7eab76e9f8ee2ebfcd552645 SHA-256: f19e531c356e66e34060b5af23165a581e6f90a0d304e3862ca0b54af64e62fd
156 Risk Score

Malware Insights

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

The PDF contains multiple links pointing to compromised websites, identified by heuristics such as 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs suggest an attempt to redirect the user to malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://sllight.ru/design/img/upload/file/lanagufomuputesopixozesod.pdf In PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a853d161a9b---34104781287.pdfIn PDF document text
    • http://iberia-ex.com/images/blog//file/pinolede.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/2cd5cb30e7acc47fa3c1827c604d01a7/77982720635.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16070c5cfca87c---nuwitenuxokif.pdfIn PDF document text
    • http://kuppersbusch-center.ru/uploads/files/35007965906.pdfIn PDF document text
    • http://novussiteyonetimi.com/uploads/file/rutikobazodiviji.pdfIn PDF document text
    • https://marblobathware.com/app/webroot/img/files/76100458298.pdfIn PDF document text
    • https://taechoclub.com/FileData/ckfinder/files/20210620_ED0714F87CE2C78D.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/d1a2eabf698323ed6567a0ff659c6972/ruvolonoxo.pdfIn PDF document text
    • http://sgadsahodayatarntaran.org/sahodyatarntarannew/userfiles/file/99197940071.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/48e91bd6766c89ce371867c0376279f1/23627405784.pdfIn PDF document text
    • http://wooshin.kr/uploaded/file/1848793951609b5e807a8c5.pdfIn PDF document text
    • http://denkobarbell.com/_upload/files/93902132829.pdfIn PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/16473757998.pdfIn PDF document text
    • http://lyshiying.com/d/files/40553001702.pdfIn PDF document text
    • http://kazuma.ru/ckfinder/userfiles/files/nimodezefizijujararo.pdfIn PDF document text
    • https://metrosecuritynepal.com/assets/userfiles/files/jeretulilinejusipov.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd89f71977c---kasezopabizafikozajunixu.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/nevupisuz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=fraszka+na+dom+w+czarnolesie+pdfPDF 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_off0000d600.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD600 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE12 18796 bytes
SHA-256: 32fb6aac1e3bc575f2fcea62bcca96c4e0ec25c87073e595df5dc45ae4c809b3
font_02_sfnt_off00011d43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D43 10896 bytes
SHA-256: baeff7a1b04b22e9f9de87a015546d2e895350053c9d1dcc305555b93a58874e