Malicious PDF — malware analysis report

Static analysis result for SHA-256 1885a543fecead35…

MALICIOUS

PDF

82.2 KB Created: 2021-09-15 23:43:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 39abad3df8ad8d0fb09f263f322b3328 SHA-1: 863b46d63af7a33c4cfd69ebe4437c0906edd677 SHA-256: 1885a543fecead351f29e761b49b88fb4a1a3e76bd01c34356b890ce94fc8b5f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV detection as a phishing trojan. The document contains a large number of embedded URLs, many of which point to disposable hosting, indicating a link farm or phishing lure. The presence of external URIs and the overall structure suggest an attempt to redirect users to malicious sites for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://crewmak.ru/uplcv?utm_term=how+to+delete+photos+from+recycle+bin+android PDF link annotation
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133979de5d41---dajufezovelasasa.pdfIn PDF document text
    • http://protezas.lt/i/File/tefajumarumewurokupapunem.pdfIn PDF document text
    • http://chiangmai-esc.net/user_img/files/67329552368.pdfIn PDF document text
    • http://akcompany.vn/uploads/userfiles/file/60828965200.pdfIn PDF document text
    • http://www.jasfec.com/imgs/uploads/18000838496.pdfIn PDF document text
    • http://rehahomecare.com/upload/editor/files/zutuboj.pdfIn PDF document text
    • https://fotojursa.cz/userfiles/file/gulavelokow.pdfIn PDF document text
    • http://www.bluefashion.cz/ckfinder/userfiles/files/najomoruwezoxepigigalive.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/45639414178.pdfIn PDF document text
    • https://www.fyna.com.au/application/third_party/ckfinder/userfiles/files/savabodozovametinijun.pdfIn PDF document text
    • https://nacituran.com/userfiles/file/bowejuvafejefafe.pdfIn PDF document text
    • http://arkystudio.eu/userfiles/files/menere.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/vumoturezanomifaji.pdfIn PDF document text
    • https://x-software.cz/data/file/20596513847.pdfIn PDF document text
    • http://hakasasi.id/userfiles/file/talewagadojez.pdfIn PDF document text
    • http://pspectr.ru/userfiles/file/45031287404.pdfIn PDF document text
    • https://saintarseny.ca/sites/saintarseny.ca/files/file/50932761700.pdfIn PDF document text
    • https://partroyfuneralhome.com/partroy/assets/file/fesopusipaxugiwuxu.pdfIn PDF document text
    • http://vanhacollection.com/images/files/kujepovisibexubona.pdfIn PDF document text
    • http://bunny888.com/ckfinder/userfiles/files/61997406644.pdfIn PDF document text
    • http://usa-ex.com/images/blog/file/pizogerizerixikenojixov.pdfIn PDF document text
    • http://pscworld.eu/ckfinder/userfiles/files/vifalezokono.pdfIn PDF document text
    • http://visusmarble.com/images_upload/files/vulipovugose.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/bilolezuwukibijiw.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161402d30ba45b---33078686340.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/26167222530.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_off0000db89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB89 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3A0 11216 bytes
SHA-256: c2f404315ffe8e60171145a85cab66ff5279e5c72d86eaacdf4b5acbce58a5f4
font_02_sfnt_off00010d85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D85 17560 bytes
SHA-256: 55c2678a81afa93a2fbd94afd37d0cd0cec0c66875d13a07f995d4c0390e4227