Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac13ff16bb0d3866…

MALICIOUS

PDF

99.6 KB Created: 2021-10-28 19:19:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8c957fa6a3b3cffdab79eb0327b8de49 SHA-1: 0ce84aebc16d130a26c2794e9c1301fe834d88f2 SHA-256: ac13ff16bb0d3866dd48788e7eb0752530503c02e6d3b10adf963da7a93fdb14
166 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The 'SE_BROWSER_INSTALL_LURE' heuristic suggests the document's content is designed to trick users into installing unwanted software, a common tactic for credential theft or malware delivery. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the lure point towards a phishing or social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://produse-zilan.ro/files/gejezuwolisatamufop.pdf In PDF document text
    • http://www.kevimotor-rock.hu/files/files/22800063435.pdfIn PDF document text
    • http://internationalelectric.ru/test/sites/default/files/file/figupupasexemex.pdfIn PDF document text
    • http://www.propper-droppers.nl/files/file/wifokerenud.pdfIn PDF document text
    • https://flomogroup.com/upload/files/tamozixefipodure.pdfIn PDF document text
    • https://laundrybyconrads.com/nbloom/fckuploads/file/77800830558.pdfIn PDF document text
    • https://phunhai.net/upload/files/29637423386.pdfIn PDF document text
    • http://inventory-acepipe.com/images/uploads/files/25601919109.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/161483f04b7da6---daxaxodofawikitabebu.pdfIn PDF document text
    • http://agierresrl.it/userfiles/files/putufupawasifefiguku.pdfIn PDF document text
    • https://bocion.com/ckfinder/userfiles/files/kitogexomuravepulawof.pdfIn PDF document text
    • https://tecnibat.net/uploads/archivos/64584443502.pdfIn PDF document text
    • http://dentalclinicbangalore.com/uploads/82003155165.pdfIn PDF document text
    • http://irs-messtechnik.at/upload/62254994240.pdfIn PDF document text
    • https://renewone.de/files/guzozitobuwuluvoxija.pdfIn PDF document text
    • https://livermore.com/wysiwygfiles/file/79606338963.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/luravagamofuvel.pdfIn PDF document text
    • http://slmj8.com/data/userfiles/files/piziwazemigamogijoke.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614f60e9115db---26687178491.pdfIn PDF document text
    • http://asavn.vn/uploads/userfiles/files/71462330088.pdfIn PDF document text
    • http://allasclub.com/campannas/file/bawipasowuz.pdfIn PDF document text
    • http://nuk-amro.de/userfiles/file/13810690373.pdfIn PDF document text
    • http://www.tomasjelinek.com/img/pub/file/wotiwijovekumadoxipi.pdfIn PDF document text
    • http://pop-around.com/file_media/file_image/file/96192944275.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/4dZi1sgP-vI/uplcv?utm_term=works+cited+chicago+style+generatorPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001058b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1058B 18760 bytes
SHA-256: 1ec796175e75be5dd5cc1b4f0ab010846e1878aa7f5d05524a0d55bbef82d8e3
font_01_sfnt_off00013605.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13605 17104 bytes
SHA-256: 381c3d712ef90fdacbbc27440ff748779d04b856b755fdef74e92487b674de79
font_02_sfnt_off00014f59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F59 10848 bytes
SHA-256: cc1cad768a4bccdc393ef9ea3393f0f1b5561347a066b5e9c3a0ffc84cb5ba79
font_03_sfnt_off00016838.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16838 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1