Malicious PDF — malware analysis report

Static analysis result for SHA-256 4942628102a6fe83…

MALICIOUS

PDF

78.5 KB Created: 2021-09-19 05:04:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a3f6034cf8d6f6b8c1056bd4adb5f94a SHA-1: 4dac233b4edc0e5c95e71aa9e18e9aa1b3485465 SHA-256: 4942628102a6fe8338d476f9337903c59339cab14e7d68a617208db669b2e4e2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment T1204.002 Malicious File

The PDF document contains heuristics indicating it's a link farm and uses a clipboard command execution lure, instructing users to paste content into a shell. Additionally, a callback phishing lure is present, suggesting a social engineering attempt. While no scripts were directly extracted, the ML classifier strongly flagged this PDF as malicious, and the presence of numerous external links points towards a potential phishing or scam campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://termosystem.pl/userfiles/file/kedofakifube.pdf In PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/26877891307.pdfIn PDF document text
    • http://dental-forum.ru/userfiles/file/74514086024.pdfIn PDF document text
    • http://vanxuantravel.com/upload/files/5455687894.pdfIn PDF document text
    • http://hyeminshop.com/DATA/files/mepegawowowukonakif.pdfIn PDF document text
    • http://aloeverajuice.cz/files/file/dafetutobovotuvabep.pdfIn PDF document text
    • http://candleelectricals.com/uploaded_files/userfiles/files/87202094664.pdfIn PDF document text
    • http://nyett.hk/uploads/news/files/280175440.pdfIn PDF document text
    • https://konteshamamotu.com/userfiles/file/26448409035.pdfIn PDF document text
    • http://german-ex.com/images/blog/file/87074791219.pdfIn PDF document text
    • http://jungam21.com/upfiles/file/1630469689.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/6565996430.pdfIn PDF document text
    • http://www.donboscovizag.org/images/files/67336328464.pdfIn PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/fosofimezazaxonasafiwa.pdfIn PDF document text
    • http://xn-----6kcaheblih5ab0a6afqbzoqe.xn--p1ai/ckfinder/userfiles/files/1266830380.pdfIn PDF document text
    • http://markjfox.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/46557937349.pdfIn PDF document text
    • http://chieucoingason.vn/files/70841624163.pdfIn PDF document text
    • http://thegioichuyendong.info/app/webroot/upload/files/65112379605.pdfIn PDF document text
    • https://anyimaker.com/upload/users/files/kegibipepelil.pdfIn PDF document text
    • https://rajatotogroup2.com/contents/files/suwizujawavoganobokol.pdfIn PDF document text
    • https://tese.in/ckfinder/userfiles/files/97002596825.pdfIn PDF document text
    • https://foulardfotografando.it/file/fupigolanijiwodojonugod.pdfIn PDF document text
    • https://thefertilizergranulators.com/d/files/luzolamux.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2388156fe---tugufekumi.pdfIn PDF document text
    • http://szpk.hu/_user/file/97178905907.pdfIn PDF document text
    • http://ccadl.com/files/20210905102334.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=how+do+i+upgrade+my+android+operating+systemPDF 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_off0000cbd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBD0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e3e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E7 10980 bytes
SHA-256: b0dd4ca8ff42bf85953be1ee3ce4aa5f283e7055180796bccb49b09a5706ef7b
font_02_sfnt_off0000fd37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD37 17920 bytes
SHA-256: a4f1e3940730a3dde935a19010a8f2243cb5a5ebc9081a310019f71ca1df9bd3