Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa3c557fff0ace70…

MALICIOUS

PDF

78.0 KB Created: 2021-03-15 02:57:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: b5df1e6bdc064dbec17b9189b7df72d9 SHA-1: cebfe0b836d14d510bb163bd6bfe8cf700b65e10 SHA-256: aa3c557fff0ace7058a54b5b12ff7a1486667adba36be06237a10cfc5c866397
126 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs, with one specifically identified as a link farm on disposable hosting, suggesting a phishing or malware distribution lure. The presence of embedded URLs and the PDF structure point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://pelibifir.ru/123?utm_term=floral+alpana+free+vector PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4413108/normal_5ffb0c5d98994.pdfIn PDF document text
    • http://jekenufakewe.mypressonline.com/zusitovujirawede.pdfIn PDF document text
    • http://shop50off.info/lord_of_the_rings_dwarf_rangersm2jun.pdfIn PDF document text
    • http://sevagawos.getenjoyment.net/jibebikupetazakazuko.pdfIn PDF document text
    • https://cdn.sqhk.co/nurijodefa/idrBlgR/clue_harry_potter_board_game_target.pdfIn PDF document text
    • https://cdn.sqhk.co/sanojuxako/jEmWuLd/murder_hornet_size.pdfIn PDF document text
    • https://cdn.sqhk.co/nelufebo/bhfJzig/92216820647.pdfIn PDF document text
    • http://volosaty100.xyz/bukezifuromemia7r5t.pdfIn PDF document text
    • http://reetodo.online/what_does_moderately_abnormal_mole_mean3c96b.pdfIn PDF document text
    • http://jobediniberine.scienceontheweb.net/free_online_french_vocabulary_games.pdfIn PDF document text
    • http://tizakeguwowil.22web.org/raneviwaturo.pdfIn PDF document text
    • http://newipufisatag.scienceontheweb.net/gevomumomunazisasiruruso.pdfIn PDF document text
    • http://nibumuxadata.66ghz.com/powerpoint_templates_for_early_childhood_education.pdfIn PDF document text
    • http://malanefire.sportsontheweb.net/49005170092.pdfIn PDF document text
    • https://cdn.sqhk.co/batitiviz/ajbgj7Y/camera_scanner_to_apk.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459325/normal_60069317d7b21.pdfIn PDF document text
    • https://cdn.sqhk.co/tevotapomow/hghfjja/solaganupibo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://lamupimifuban.onlinewebshop.net/data_science_and_big_data_analytics_wiley.pdfIn PDF document text
    • http://gusutawidike.epizy.com/56525080501.pdfIn PDF document text
    • http://dovunufesesiz.onlinewebshop.net/borusidukedajenusaweful.pdfIn PDF document text
    • http://jonufinufezo.epizy.com/lugopawatik.pdfIn PDF document text
    • http://dotopaku.atwebpages.com/estudio_biblico_de_la_oracion_del_padre_nuestro.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
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off000105a6.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x105A6 16544 bytes
SHA-256: 7987de1b603f0b3f5038701c4c56272af2f4caa150da6aa6a56cefaa9de2421e
font_00_sfnt_off0000d49e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD49E 4588 bytes
SHA-256: 71594f4792c7fe0d7e840791ba741a7f7485f0388bb09e00f2feeacb97b3f3f4
font_01_sfnt_off0000e443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE443 9704 bytes
SHA-256: 029e86eff16076b1f25075cfef3b82eb5b6e740619b60ba2dae2873aa1c144d6
font_03_sfnt_off00011c5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C5C 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361