Malicious PDF — malware analysis report

Static analysis result for SHA-256 ed6ecd2b10dc5c1a…

MALICIOUS

PDF

71.6 KB Created: 2021-04-20 19:27:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8961cef3115dabdcbae70a23f27e5fc3 SHA-1: 7b6ed26b99b0d3e947f0ea5bf4cd6e9ee1a3cda6 SHA-256: ed6ecd2b10dc5c1a91ff0d00645d2d84e119731a07849e0b250bd932c743c6fe
96 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are to PDF files, suggesting a link farm or SEO spamming tactic. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the PDF structure and embedded URLs indicate a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 4

  • 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.
  • 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://jumiwimov.ru/strik?utm_term=flying+fairy+charging+instructions
    • http://promoocaoameericanas.com/abecedario_chino_espaol4pruw.pdf
    • https://cdn.sqhk.co/zasokolof/hfohdmf/real_steel_robots_game_download.pdf
    • http://copyrightprivacy.site/347979499386bm5m.pdf
    • https://cdn.sqhk.co/nomitusibop/j4R4mpi/real_craft_3d_apk.pdf
    • http://bekopomulasebi.getenjoyment.net/52591499844.pdf
    • http://appletopshop.ru/520068604384aov.pdf
    • http://pagebake.com/sejend1g1x.pdf
    • http://izzzaaa.space/defuse_the_bomb_bungee_rugby_ballys72h.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/lurutopobi/zuzewinozikavab.pdf
    • https://s3.amazonaws.com/daraniwekamidir/lijutuzom.pdf
    • https://s3.amazonaws.com/dejazuvorira/paint_by_numbers_custom_photo_amazon.pdf
    • https://s3.amazonaws.com/mokuwanibof/14471145613.pdf
    • http://gizixaxeviduf.myartsonline.com/hydraulic_accumulator_nptel.pdf
    • http://kuxoxokazutuv.myartsonline.com/when_berserk_will_end.pdf
    • https://s3.amazonaws.com/lolaritemukole/do_you_put_a_comma_before_inverted_commas.pdf
    • https://e9abb47e-19e5-4ec2-9f3c-2aa4e6f2bf0a.filesusr.com/ugd/92be99_16f29da0c17e4ea0a6681f08f2785855.pdf?index=true
    • https://0f926834-650c-4d5a-b53c-ad60ae412ccc.filesusr.com/ugd/6a44d8_fe93a590f82f485f94acf16feb72768e.pdf?index=true
    • 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
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c803.bin
45713111fce5f133293f0cfb5b5bcc81f18909a8b56b6db55c778ad3738138bf
pdf-font-stream PDF embedded font (sfnt) at offset 0xC803 5200 bytes
font_01_sfnt_off0000d9c3.bin
f9fa010a164ba4bf0993a462f82bc30eb633c685faab2b089113f1b1eb680951
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9C3 10156 bytes
font_02_sfnt_off0000fcd8.bin
354dce64f07f3d7acdf6a04edf763950ffbfec4edcbb4bfe17b65a83544077bb
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCD8 16036 bytes