Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b88dc8e33eab163…

MALICIOUS

PDF

74.0 KB Created: 2021-09-15 20:29:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: da5917c1a3de37a4313128b5666696ab SHA-1: f30851511c9a04f98afd0748e1286e6ff741e7b0 SHA-256: 6b88dc8e33eab163fba5695f643c6bd3fe2adf59aaaa4dacd631aa3559ff7b51
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Multiple embedded URIs, including one pointing to a raw IP address and others hosted on compromised WordPress sites, suggest an attempt to redirect users to malicious content. The PDF document body is unreadable, but the heuristics strongly indicate a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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 https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/avc9oi8lc5l5v08h1irp8qo2l4/98925899784.pdf
    • http://vattucongtrinh.com/userfiles/file/lagepasirozofasen.pdf
    • http://sp2wronki.pl/fotki/fotki/file/48703892658.pdf
    • http://esistore.be/userfiles/file/kezazonuv.pdf
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/f337cd4219313c0ca16297105bae91e1/rakozogagu.pdf
    • http://morebricks.com/ckfinder/userfiles/files/xulojadanexalapirejadixo.pdf
    • http://tsradviseurs.nl/mailing/images/photo/file/82967898200.pdf
    • http://cl-metalparts.com/d/files/62323053561.pdf
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/4a5c23191a02d0d5ca6216796f2e235a/20307247321.pdf
    • https://mtestbd.com/assets/uploads/files/kevifowa.pdf
    • http://emanuelmlevin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gegowoluz.pdf
    • http://aurastaffing.es/upload/file/38920338730.pdf
    • https://sthouseluxury.com/upload/files/67472861954.pdf
    • https://underworldgear.com/admin/images/fckImg/file/11258310062.pdf
    • http://law885995.com/upload/fckimages/file/54520621363.pdf
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/857b53dda18de936db155e60b17f4814/domor.pdf
    • http://157.230.241.115/image/upload/File/57543458386.pdf
    • http://hanhthien.net/uploads/file/68025605122.pdf
    • http://www.peritaonline.es/ckfinder/userfiles/files/47245434928.pdf
    • http://darslaska.org/ckfinder/userfiles/files/goxuvuxarumaroku.pdf
    • http://dd-eng.com/files/files/nekefulelawuvilev.pdf
    • http://imoroz.by/upload/file/99925806246.pdf
    • http://brno-skoleniridicu.cz/ckfinder/userfiles/files/42845141071.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=silent+camera+app+for+android
    • 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://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_off0000bc96.bin
92b9cd3e512278cbbaa91a848a5bef3cce7b8b9a03ce212f2d061f8ef6364599
pdf-font-stream PDF embedded font (sfnt) at offset 0xBC96 17668 bytes
font_01_sfnt_off0000ea52.bin
f9353882efdfe81dd58d8aa473595095d1fb5bb4da16e1feedad4cdf0bcaaa5f
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA52 10688 bytes
font_02_sfnt_off000102c3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x102C3 16792 bytes