Malicious PDF — malware analysis report

Static analysis result for SHA-256 eb54252603f2d57b…

MALICIOUS

PDF

95.3 KB Created: 2021-09-02 13:47:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 303d1a3d6f9f32e15ff590c26ef2e9c5 SHA-1: ec7fad08efc93ecc1620bfc392aae265d5e07937 SHA-256: eb54252603f2d57bcfdca6e6a6452b64bd9d340b4ee23b87f6ccb44c44a5ce2b
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous external PDF files hosted on various domains, several of which are flagged as potentially compromised or disposable. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for SEO poisoning or distributing further malware. No scripts were extracted, but the structure and URL patterns suggest a phishing or content distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://suamayin.biz/userfiles/file/923563803.pdf In PDF document text
    • http://ohmytour.kr/FileData/ckfinder/files/20210830_B3CB364775287799.pdfIn PDF document text
    • http://zhhyhb.com/uploadfiles/files/79056827478.pdfIn PDF document text
    • http://connect-senior.ch/uploades/userfiles/file/mudusobuz.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/64778086630.pdfIn PDF document text
    • http://dainindo.com/Uploads/userfiles/files/ragarilafidax.pdfIn PDF document text
    • https://baobihungphu.com/media/ftp/file/gurusorapiruzuju.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f047340c7f---vuwedabosemiragisu.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/saxumunozuwuvijunaliga.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/4e95da4e205f91f54326af6bc5678e33/vobepixexonefopatumo.pdfIn PDF document text
    • http://mmbc.cz/_data/user_files/file/mesujukunumomo.pdfIn PDF document text
    • http://uctodane.cz/UserFiles/File/10579811876.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/ditaladegisejoguzimekuxip.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/mefoner.pdfIn PDF document text
    • http://avandcie-automation.fr/ckfinder/userfiles/files/28278990294.pdfIn PDF document text
    • https://postelezmasivu-olomouc.cz/ckfinder/userfiles/files/4884340517.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/10f460a9f8953348aa058aabba571cce/17641043564.pdfIn PDF document text
    • http://merklink.nl/site/data/ws/files/faropep.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/vawoposamapuko.pdfIn PDF document text
    • http://tutaylamhet.com/storage/ckfinder/files/68469463214.pdfIn PDF document text
    • https://wineuniverse.us/userfiles/file/90843057725.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/9cc3149e9a95144efa526a4d785775fa/98488267924.pdfIn PDF document text
    • http://huntland.hu/upload/file/6042679155.pdfIn PDF document text
    • https://akapacha.com/userfiles/file/80111195152.pdfIn PDF document text
    • http://istanbulballoons.com/ckfinder/userfiles/files/31161614586.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=bomba+para+fumigar+de+espalda+manualPDF link annotation
    • 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_off00010df4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF4 11036 bytes
SHA-256: 49227f2987612c065ae15557a2524d7cf1533da45f9809f2233cb168703b76a7
font_01_sfnt_off00012723.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12723 18460 bytes
SHA-256: d4f88106ad0b06cbf852613ca5b81d25c3512142f16a84513286059e8086d405
font_02_sfnt_off000155af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x155AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1