Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8eb10ad7d21b2bc…

MALICIOUS

PDF

72.0 KB Created: 2021-10-04 10:49:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 757d629b3ca4c869713e745a104407c1 SHA-1: 47b66cec4c42c3b0d68615e0d0cd2b771ed2ced3 SHA-256: c8eb10ad7d21b2bcd2137e1cf7b92d280be7cdb56a2ca20c48aaa337ffbdb6ed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics indicate the PDF functions as a link farm, directing users to potentially compromised WordPress uploads and other external sites. While no scripts were directly extracted, the nature of the link farm suggests an intent to redirect users to phishing or malware hosting sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/pehsc8etug47q73o85kt06pj9a/milag.pdf In PDF document text
    • https://radiosmile.hu/upload/file/6274214043.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/81412653434.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/161312cc72dd20---lidojowepenat.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/4144647047.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/35212335219.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/b6c378c02c218974f587d6048b61d7f3/99140499660.pdfIn PDF document text
    • https://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/39486188846.pdfIn PDF document text
    • http://www.leasebridge.com/CKUPimg/files/fuzugafixonazemib.pdfIn PDF document text
    • https://petroservice-eg.com/userfiles/file/79682130574.pdfIn PDF document text
    • https://garraldaarquitectura.com/garralda_userfiles/files/7108698787.pdfIn PDF document text
    • http://botaierpharm.com/upload/files/juwuxodogebowosut.pdfIn PDF document text
    • http://borik.customreal.sk/data/files/4814522173.pdfIn PDF document text
    • https://quatden.vn/webroot/img/files/vifuduzufobagotawap.pdfIn PDF document text
    • http://ydtmuhendislik.com/ckfinder/userfiles/files/wixobesebakobuteku.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/96573293368.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/7541496247.pdfIn PDF document text
    • http://faisaltowel.com/survey/userfiles/files/javugukaretefafosakeg.pdfIn PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/pimajiz.pdfIn PDF document text
    • http://keletunderground.hu/images/uploaded_pics/file/wafozeji.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/161387d5079330---24404801888.pdfIn PDF document text
    • https://zhbiotech.com/CKEdit/upload/files/82479527254.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/weput.pdfIn PDF document text
    • http://eksternest.be/images/file/remipi.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1614ee61e3eb1b---duzimareribapatinezenigel.pdfIn PDF document text
    • http://vinacafe-dalat.com/Images_upload/files/lusonopubarubazelidafima.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=the+meaning+of+thermodynamicsPDF 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_off0000b532.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB532 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD44 17056 bytes
SHA-256: 4a926d92522b1701682b50fdbf65beafa0c4fd4d17b2bc82bde5f3bef67ea600
font_02_sfnt_off0000f94b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF94B 10956 bytes
SHA-256: 37a518b20c45283c669ec1073bb7b0aae9f80ab52749eeb6e9f78e89ab976f00