Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d812d881d448c56…

MALICIOUS

PDF

84.2 KB Created: 2021-09-19 20:55:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fede15bc054bba47a8877ef4e9e0b073 SHA-1: 810f8eabe02f945eed8924a78f4f9acb0052b050 SHA-256: 1d812d881d448c5655faa573387695939a7615759a665ae26d5e00a5055e1b8d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as a malicious PDF by multiple heuristics and an ML classifier. It contains numerous external URIs pointing to various domains, suggesting a link farm or phishing lure. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate attempt to obscure the true destination or spread links across disposable hosting. While no scripts were explicitly extracted, the PDF structure and numerous embedded URLs strongly suggest an intent to redirect users to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crewmak.ru/uplcv?utm_term=jungle+cruise+old+movie PDF link annotation
    • https://iaido-iaijutsu.ru/userfiles_exc/38401650711.pdfIn PDF document text
    • https://cylinder96.ru/admin/ckfinder/userfiles/files/rovedaz.pdfIn PDF document text
    • http://lawfirm.vn/MINH/user_files/file/diwokimowamirerulis.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202109122317517419.pdfIn PDF document text
    • http://shopsuathientu.com/uploads/userfiles/file/23067059736.pdfIn PDF document text
    • https://posetili.ru/userfiles/file/94931672152.pdfIn PDF document text
    • https://uangraja.com/contents/files/tagokoxikidukixov.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140ce6721238---volugozuwotuxupiruwakixi.pdfIn PDF document text
    • http://thefarmatarapahoecounty.com/userimages/lozofagafasib.pdfIn PDF document text
    • http://kurier48.pl/files/userfiles/file/87577429558.pdfIn PDF document text
    • http://razzledazzleevents.in/userfiles/file/12683940710.pdfIn PDF document text
    • http://somkuthyoptika.hu/editor_up/39485534556.pdfIn PDF document text
    • http://goang-hann.com/uploads/files/202109081357255535.pdfIn PDF document text
    • http://kernenshepler.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kusej.pdfIn PDF document text
    • https://mtestbd.com/assets/uploads/files/bafamuxikawuxajozolopel.pdfIn PDF document text
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/76857988389.pdfIn PDF document text
    • http://shuimotongyuan.com/userfiles/file/1576808469.pdfIn PDF document text
    • http://xn--h49al33a2zdp0eo1x.com/DATA/file/20210917094532.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161398443c87a7---bikegabumilaposof.pdfIn PDF document text
    • https://www.nvsrolko.org/ckfinder/userfiles/files/44123848218.pdfIn PDF document text
    • http://japanbizkorea.com/userData/ebizro_board/file/72320908262.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/fibeposelefurez.pdfIn PDF document text
    • https://textosolutionslinguistiques.ca/upload/editor/file/6163022658.pdfIn PDF document text
    • http://ihanzao.com/userfiles/file/20210907144353_1632117619.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_off0000e3c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fbd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBD8 18208 bytes
SHA-256: d3f3078481966c5f43da14490738ff99d2a9e086df3502f26b6cc070a76ec886
font_02_sfnt_off00012af9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AF9 10612 bytes
SHA-256: e61f7fdf96f6d89aa5df1043e5cfec5d8b10ed1eba29f3e97ec9bfc300294a94