Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa2c4e91141bd6d2…

MALICIOUS

PDF

68.0 KB Created: 2021-09-15 11:44:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: aae1cdb2353ffe64730518e33b691e08 SHA-1: 2f44ddaacde0bfd9d4f9b7cb81c14dcdbb856b85 SHA-256: aa2c4e91141bd6d21180fa0459660822e80b8ef5b3e831370c94c856fdd0cd83
116 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as a malicious screenshot lure, typical of phishing campaigns. It contains numerous embedded URLs pointing to various domains, some of which appear to be compromised WordPress sites. The ML classifier strongly indicates maliciousness, and the structure suggests an attempt to trick users into clicking through to a potentially harmful destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 6

  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://ketchas.ru/uplcv?utm_term=muscular+system+organs PDF link annotation
    • https://okazdedziecko.pl/_files/Media/file/42980616047.pdfIn PDF document text
    • http://preiswerte-unterkunft-papenburg.de/mediapool/63191807684.pdfIn PDF document text
    • http://xaydunghoangthanh.com/img_duhoc/files/javewitoxujawu.pdfIn PDF document text
    • http://lawyermo.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bapitikiwabujej.pdfIn PDF document text
    • http://labonguyenhoang.com/img-chamthi/files/44854866189.pdfIn PDF document text
    • https://dcicz.org/userfiles/file/7001668404.pdfIn PDF document text
    • http://lindendirect.com/ckfinder/userfiles/files/nogoxujawulobapi.pdfIn PDF document text
    • http://xinyuemu.net/assets/202109/files/20210908113512843472.pdfIn PDF document text
    • https://prosaison.fr/userfiles/files/76471382226.pdfIn PDF document text
    • http://westernstudioservice.com/admin/userfiles/file/tiwibedodewapemiz.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/161417ad4c5813---fisobeviwusosabigewuw.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/vateramugozumofezup.pdfIn PDF document text
    • https://tbsva.org/Upload/files/20210906173131.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/51e3fe849c9c05f491c6b414c0778056/90112472808.pdfIn PDF document text
    • http://unseenadventure.com/userfiles/file/kilanupavunosele.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/lesawujezetupevanodilupim.pdfIn PDF document text
    • http://lesbambousbleus.fr/ckeditor/upload/files/55034993581.pdfIn PDF document text
    • https://jewfri.kr/files/image/files/73401146241.pdfIn PDF document text
    • https://sunpower.lv/ckfinder/userfiles/files/11994279924.pdfIn PDF document text
    • https://phuketwebstudio.com/ckfinder/userfiles/files/lawekuziviz.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613522ad4b272---befodutapoliwozame.pdfIn PDF document text
    • http://bunny888.com/ckfinder/userfiles/files/26812650663.pdfIn PDF document text
    • http://allivecoat.com/userData/board/file/mubofatuzagadanezomanuvaj.pdfIn PDF document text
    • 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_off0000af9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF9F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7B6 10688 bytes
SHA-256: e5382c4f3b05907059ab2fc36e408519dfb6646c51a6b6c8b25bb5b982e77231
font_02_sfnt_off0000e055.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE055 14032 bytes
SHA-256: 9c25d9b3640b322395caccb0ea212a114d6202de2ca0bbdc435836a21407a177