Malicious PDF — malware analysis report

Static analysis result for SHA-256 431ddee4dd10f7c4…

MALICIOUS

PDF

83.7 KB Created: 2021-09-16 03:31:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0d83cbe1e8137ded4b539e4604bb85c8 SHA-1: 44b73bcf3721eafac0afac32a31cf5495fe1dbd5 SHA-256: 431ddee4dd10f7c4eb69e2c15ab1eac6bef0f905f079dc68e3711a83190628f0
156 Risk Score

Malware Insights

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

The file is a PDF document identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The heuristic firings indicate that this PDF functions as a link farm, likely intended to redirect users to phishing sites or download further malware. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://garglob.ru/uplcv?utm_term=redmine+android+app PDF link annotation
    • http://www.zywawiara.pl/pliki/69011708920.pdfIn PDF document text
    • http://vakoplus.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/rebebepokonafiro.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/42141123279.pdfIn PDF document text
    • http://rewitex.pl/userfiles/file/derugutowokalekakamare.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613a915a204d4---29798549304.pdfIn PDF document text
    • https://conrays.ru/f/data/91097562908.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142781aa0761---gesosuzobigajatetev.pdfIn PDF document text
    • https://cafesca.info/ckfinder/userfiles/files/veboguwud.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161376945d9f73---67763751239.pdfIn PDF document text
    • https://joinvita.com/neu/userfiles/file/15758271955.pdfIn PDF document text
    • https://infotechloyalty.com/bot/ckfinder/uf/files/73784392310.pdfIn PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/zedamoriwozibirabatude.pdfIn PDF document text
    • http://seghers.kr/data/editor/file/2084425843613c36d38567a.pdfIn PDF document text
    • http://grupophi.es/uploads/files/vabazatomot.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/53778381232.pdfIn PDF document text
    • http://czytamzezrozumieniem.pl/userfiles/file/wuxofuxixadutagimusezazil.pdfIn PDF document text
    • https://eetravel.net/file/32634236084.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16140d4c3e8e6f---zalekulagudikoxuki.pdfIn PDF document text
    • http://szerecsengyogyszertar.hu/editor_up/rixafobadatewaseseba.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/jevopuxobovupesarobunamam.pdfIn PDF document text
    • http://jujucuisine.com/userfiles/file/pofalakijekowujusivibo.pdfIn PDF document text
    • 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_off0000e3ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3BA 10288 bytes
SHA-256: 281250b30299078fce438fea709c038d7dd8296ee50b1bfd9957054460540748
font_01_sfnt_off0000fabd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFABD 18056 bytes
SHA-256: c581e8146d8a20e5f3078f286b0cfe0e2fe3352b2c8e6a379fed997f545a01e0
font_02_sfnt_off0001299c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1299C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1