Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1cddfa63535576d…

MALICIOUS

PDF

79.2 KB Created: 2021-09-08 23:01:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 9aa38e008a486edde3dbdde19a270b67 SHA-1: fcd8da071dae057423a1146b7121995db6de314b SHA-256: b1cddfa63535576d537037fd4f3b4a7a5940b8a2d899e0a11cb7f3ef82ce626d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous external URLs, with one prominent URL being `https://coretry.ru/uplcv?utm_term=android+developer+speech+to+text`, suggesting it is used as a lure to redirect users to potentially malicious content. The PDF structure itself is also identified as a link farm on disposable hosting, further supporting its role in a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://coretry.ru/uplcv?utm_term=android+developer+speech+to+text PDF link annotation
    • http://fitsiluet.cz/data/file/zoxikofifeduperomapebim.pdfIn PDF document text
    • https://samavetpharm.com/userfiles/files/suzamiluzojir.pdfIn PDF document text
    • http://lpkgoodframeupvc.com/userfiles/files/boxak.pdfIn PDF document text
    • https://infotechb2blite.com/bot/ckfinder/uf/files/62140024963.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/161319f3a87845---dubapusixakotuli.pdfIn PDF document text
    • http://superazs.ru/images/news/file/goduni.pdfIn PDF document text
    • http://metapolar.hu/tmp/22196357357.pdfIn PDF document text
    • http://peknanevesta.sk/media/file/39284372799.pdfIn PDF document text
    • https://securitydm.rs/slicice/file/2509668599.pdfIn PDF document text
    • https://curtain.jinware.com/upload/files/53585237205.pdfIn PDF document text
    • http://cdn.eagle.mn/uploads/userfiles/files/87479839544.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/47369428261.pdfIn PDF document text
    • https://jatransfer.com/userfiles/file/95965713106.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/e7742feaa6ceb4451a2022bf46af2b94/83552007374.pdfIn PDF document text
    • https://oncetrabzon.com/resimler/files/28331547750.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/kotuvesagumanif.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/53171450781.pdfIn PDF document text
    • https://happyjourney.webtrails.in/ckfinder/userfiles/files/16568299394.pdfIn PDF document text
    • https://lecachet.fr/docs/files/37207344775.pdfIn PDF document text
    • https://gedayapi.com/userfiles/file/bomebijoborunorabumisol.pdfIn PDF document text
    • http://istanbulballoons.com/ckfinder/userfiles/files/25009583502.pdfIn PDF document text
    • https://huaku3c.tw/uploads/files/202109020151293127.pdfIn PDF document text
    • http://remont-etalon.ru/upload/files/xosuwowawox.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_off0000d20a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD20A 10596 bytes
SHA-256: 96ef463c94e31aa6e7f28c470c5d1f692713d4ad67dc25e115c26b63bb15cb5a
font_01_sfnt_off0000ea2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA2C 17464 bytes
SHA-256: b0a265bbceb3b581dd9b79292e21e9eb593fa698fcf9bfe81a0acff2a258e879
font_02_sfnt_off0001173c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1173C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1