Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f31b90f18fb0097…

MALICIOUS

PDF

74.0 KB Created: 2021-03-29 21:54:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7e56ee022f0085862573c7e68f6d5fbf SHA-1: 7b697226fb75b965c548cafe5c7c7565f713a5d8 SHA-256: 4f31b90f18fb0097b7034efedcbf0996fca16ba15dda298ca55f84d757e572bd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious. It contains a large number of external links, many of which point to PDF files, suggesting a link farm or phishing attempt. The document body, though heavily obfuscated, indicates a lure related to 'build an atom worksheet key'. No scripts were extracted, but the presence of numerous external URLs suggests the primary function is to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://dafemum.ru/wix?keyword=build+an+atom+worksheet+key
    • https://cdn.sqhk.co/kuwusemob/ChJqhfz/maxeruzigijuk.pdf
    • https://cdn.sqhk.co/kawinojos/a8QEvtj/thumbelina_movie_1994.pdf
    • https://cdn.sqhk.co/jakufomego/RvEgdNL/rusolovulupatoxirukolamet.pdf
    • http://pixidilivutep.medianewsonline.com/57529080410.pdf
    • http://livetajo.22web.org/linunetijexiti.pdf
    • https://jamakebowixon.weebly.com/uploads/1/3/4/4/134477175/dibukij.pdf
    • https://lojavexir.weebly.com/uploads/1/3/5/9/135963097/miraxatop.pdf
    • http://jarewitof.mypressonline.com/diccionario_catalan_castellano.pdf
    • https://vutizimowunofe.weebly.com/uploads/1/3/4/3/134354130/1654838.pdf
    • https://cdn.sqhk.co/vugasoveg/pjejdjc/12550511313.pdf
    • https://cdn.sqhk.co/nuvexajamu/ivgehdV/30971409237.pdf
    • http://gomijojupi.iblogger.org/el_alquimista_de_paulo_coelho_descargar.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://limuzer.atwebpages.com/wetibi.pdf
    • http://vitivewizonomaw.epizy.com/wotitarexipemi.pdf
    • https://uploads.strikinglycdn.com/files/5d6a2464-ca74-4ac2-acde-c2a091d3c1d9/bafisafegut.pdf
    • https://uploads.strikinglycdn.com/files/e4f0296f-8003-43e1-b1ef-64a68de8a97f/unix_command_cheat_sheet_vi.pdf
    • https://s3.amazonaws.com/vavale/cutover_migration_exchange_2007_to_office_365_steps.pdf
    • https://s3.amazonaws.com/bisiku/is_openoffice_still_free.pdf
    • https://s3.amazonaws.com/toliwudalamem/98689763342.pdf
    • https://s3.amazonaws.com/marimejerebo/pr_best_practices_for_seo.pdf
    • https://s3.amazonaws.com/toniseligiwuzux/8575868441.pdf
    • http://rovunebezub.epizy.com/nuwixetumopori.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e114.bin
159a81cb96f5df2fd0be33dbc539ab2bdc0b4219a37c0c2c4a551fd0ba66b152		 pdf-font-stream PDF embedded font (sfnt) at offset 0xE114 5372 bytes
font_01_sfnt_off0000f343.bin
9558a8143ee70d00f5573411bdeb966caa68991ee119c155ab318adf69b17a7c		 pdf-font-stream PDF embedded font (sfnt) at offset 0xF343 12252 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.