Malicious PDF — malware analysis report

Static analysis result for SHA-256 d50bd0f35dd332e2…

MALICIOUS

PDF

80.5 KB Created: 2021-09-07 17:52:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c8c5e1ca6eee1b35c41181ec98aa374c SHA-1: 78ca9b16187c71ae4eefab04c252eafd17e66ff7 SHA-256: d50bd0f35dd332e27f9641c7096aa8246efe3592e530634d29a91b038592866d
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised CMS upload storage or disposable hosting. The primary goal appears to be directing users to external sites, potentially for phishing or SEO spam.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://computer-rudolstadt.de/upload/file/21026834568.pdf In PDF document text
    • http://kezmosas.hu/files/file/refavivajafakubaj.pdfIn PDF document text
    • https://artenika.pl/fck/file/9080748271.pdfIn PDF document text
    • http://ellissi.org/userfiles/files/10771249112.pdfIn PDF document text
    • https://facades-et-traditions.com/actualites/file/bukupirasuxezikuw.pdfIn PDF document text
    • http://rudolphalexander.com/uploads/files/jitekutibexolukimubilev.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160df37fe42b18---rodabijulezozowu.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/r0atj8fl89j2opvb25dgsvsth6/25522224482.pdfIn PDF document text
    • http://moscowprice.com/content/xuploadimages/file/sisetivifaxos.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160dc8c769b0e9---71240085217.pdfIn PDF document text
    • https://koncnc.com/genelresimler/file/siwezederosorunemeka.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/879207bf1661c1eba7b0645dd9defdeb/82976653211.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/ca5fe051dee43f2bf4ef6e86a1351ec8/45420971355.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ab49248f318---4164850240.pdfIn PDF document text
    • http://yuhenganquan.com/userfiles/file/20210524232056_955430943.pdfIn PDF document text
    • http://palestraarkadia.it/userfiles/files/75077317617.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021061805121773499.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b277089c860---23619097395.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b60f7b7093d---18777205022.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16107ae26e449a---mameritijiku.pdfIn PDF document text
    • http://meghdoothsuzuki.com/uploads/59801192264.pdfIn PDF document text
    • https://etimes.mn/uploads/files/11023167017.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/028a075b674ac066fdbcb173f81c0c9d/kosadomuzawemo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=breville+ikon+juicer+manualPDF 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_off0000d49e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD49E 18052 bytes
SHA-256: 9f8462911d0c54ada136408e73d1380e60340dd5d2efbb17d9f3feec063ec0f1
font_01_sfnt_off000102ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102CE 10568 bytes
SHA-256: ee80b0e9104bf4f7181c2667577e6a18e0903affd8bdc2e870b510f4cfd5154d
font_02_sfnt_off00011ad4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AD4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1