Malicious PDF — malware analysis report

Static analysis result for SHA-256 83a93e9f2e75ad80…

MALICIOUS

PDF

82.8 KB Created: 2021-09-16 18:01:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 5698bf133514d0a01f2d20b48aea8220 SHA-1: 87e00ff59ab6214173eef2f3c1ae96bfa68a2e58 SHA-256: 83a93e9f2e75ad80c54fcbfa90b88649c42e04ff028851404eda2472a9555974
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to various domains, and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic suggests these are used to create a link farm. While no scripts were explicitly extracted, the presence of external links and the link farm heuristic strongly suggest the document's purpose is to redirect users to potentially malicious websites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://jl-vacuum.com/upload/files/84059817224.pdf In PDF document text
    • https://casalindasbakery.com/ckfinder/userfiles/files/11094413030.pdfIn PDF document text
    • http://gibisch.biz/files/files/18782826629.pdfIn PDF document text
    • http://aokunoil.com/ckfinder/userfiles/files/13979883463.pdfIn PDF document text
    • http://sibstroiexp.ru/userfiles/file/gavedojoxuxarugi.pdfIn PDF document text
    • http://innotack.com/userfiles/files/1186663724.pdfIn PDF document text
    • https://giolog.biz/images/bulk_images/files/vixiduditukoromuvexulo.pdfIn PDF document text
    • http://solarhomepage.ch/fckeditor/editor/images/file/zapemiwuvimojis.pdfIn PDF document text
    • http://lmleadmanagement.com/userfiles/files/11640016006.pdfIn PDF document text
    • http://collectifff.be/imgdb/accueil/files/59842765543.pdfIn PDF document text
    • https://pataniforum.com/admin/jquery/ckfinder/userfiles/files/baboludi.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613508141674b---96403802958.pdfIn PDF document text
    • http://studiorapizza.it/userfiles/files/bevibaw.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/36283364777.pdfIn PDF document text
    • https://www.hasmow.com.au/application/third_party/ckfinder/userfiles/files/jimikoneradavodejed.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/sojenusopiwubokajes.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/kogugilagul.pdfIn PDF document text
    • https://corpusbg.com/files/fck/file/diweliroxarijumuve.pdfIn PDF document text
    • http://mpu-beratung-brendle.de/userfiles/file/lumoneja.pdfIn PDF document text
    • http://1yunnan.com/ckfinder/userfiles/files/38312316676.pdfIn PDF document text
    • http://fantasymusic.it/userfiles/files/zitad.pdfIn PDF document text
    • http://alituncer.net/userfiles/file/89297312356.pdfIn PDF document text
    • http://9y.bfage.com/upload/files/20210914102153.pdfIn PDF document text
    • http://roycraft.ca/userfiles/file/64691334530.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=open+browser+in+mi+tvPDF 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_off0000d94e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD94E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF160 19836 bytes
SHA-256: da19fe1114fa2638f912ca7ea423993f9d5d1cd4ae468e51e15e1407eeedd653
font_02_sfnt_off00012581.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12581 10520 bytes
SHA-256: 2a03def242494d7f1a55d7fb5b3200c3d9a5181a50ec92e51609f1d2a30e51c7