Malicious PDF — malware analysis report

Static analysis result for SHA-256 24c129fd41474fd4…

MALICIOUS

PDF

87.5 KB Created: 2021-09-09 20:57:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: a24067f7775018820c46b5e708218043 SHA-1: 7efe7f8001c256ab3619922bdfdc5d108e6bd8cf SHA-256: 24c129fd41474fd4a7a9050743494177a2f01695c9f6f307bd1a3c3b244a7513
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded links, many of which point to disposable domains and one known malicious redirector. The ML classifier strongly indicated maliciousness, and the link farm behavior suggests an attempt to lure users to potentially harmful sites. No scripts were extracted, but the primary function appears to be redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://ketchas.ru/uplcv?utm_term=android+sniff+network+traffic In PDF document text
    • http://cosyromania.com/media/file/88457241214.pdfIn PDF document text
    • http://areopag-group.ru/sites/default/files/uploads/vilomaledujibugametaxoki.pdfIn PDF document text
    • https://nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/dufeluxemadigogefenunaw.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/e1cfdb7422f7dfda079251b3419ca9d3/xopojeredatitazix.pdfIn PDF document text
    • https://jakspravnenapsa.cz/userfiles/file/54369698420.pdfIn PDF document text
    • http://xn--82cac8d3ajrc0gd0bo4a7nf3qg.com/userfiles/files/30598582502.pdfIn PDF document text
    • http://www.likoda.com.tw/upload/ckimg/files/vozid.pdfIn PDF document text
    • https://aicpwdosaeast.com/ckfinder/userfiles/files/sapipujujikozajudavo.pdfIn PDF document text
    • http://yenidenyuzlendirme.com/ckfinder/userfiles/files/91115489421.pdfIn PDF document text
    • http://timeyear-v.com/userfiles/file/61850134335.pdfIn PDF document text
    • http://brezov-gaj.si/uporabnik/file/69651721376.pdfIn PDF document text
    • http://achilleferolla.it/userfiles/files/51375186534.pdfIn PDF document text
    • http://chaodontuonglai.vn/uploads/ck_upload/files/sazasabuwefukusupazere.pdfIn PDF document text
    • http://terralis.eu/catalogue_dynamique/file/wofinara.pdfIn PDF document text
    • http://seowonbattery.com/files/fckeditor/file/2930458226133290f0eef7.pdfIn PDF document text
    • http://ros-grad.ru/fck_editor_files/files/rezemap.pdfIn PDF document text
    • http://abwingssuffolk1.com/uploads/files/54806012540.pdfIn PDF document text
    • http://diagcorlifescience.com/attachment/file/pitasexanu.pdfIn PDF document text
    • http://saga.diamonds/uploads/ckfinder/files/tidipalodipaluxefelaxeja.pdfIn PDF document text
    • http://skipjackpoke.com/ckfinder/userfiles/files/japunidinaz.pdfIn PDF document text
    • http://condosworld.com/abisol1/userfiles/files/fudekirokeruw.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_off0000f0b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000108cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108CC 10584 bytes
SHA-256: 69da8ff86d090ef3c1d2dc40b3929757ffc92d3cf815a2a2e166b9b0cfdbdb12
font_02_sfnt_off00012132.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12132 18108 bytes
SHA-256: 9c03b7f74e1cbdf7a1c09a0143c27b53488ae654b876473627f3c1880fa743d1