Malicious PDF — malware analysis report

Static analysis result for SHA-256 1641ba356cf32f17…

MALICIOUS

PDF

68.0 KB Created: 2021-09-30 14:55:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 294f11908c29faa6ea5573d2103faca0 SHA-1: 878cfdd4ebd51a799a99f08fe69a5d84c67dd5a2 SHA-256: 1641ba356cf32f17c57aaef469ccbd77354aa717854a470047dd71fe5944ffb0
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF exhibits characteristics of a phishing lure, including being image-only with a clickable action and hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URLs, such as https://laborke.ru/uplcv?utm_term=wifi+wps+unlocker+for+android+9, are likely used to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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
  • 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 67 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://laborke.ru/uplcv?utm_term=wifi+wps+unlocker+for+android+9 PDF link annotation
    • http://fohow77.ru/upload/file/24099855261.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/tejugem.pdfIn PDF document text
    • http://bogaarchitetti.it/userfiles/files/51657412011.pdfIn PDF document text
    • https://designclarf.it/file/74805075076.pdfIn PDF document text
    • https://0924055971.com/uploads/files/202109231737489772.pdfIn PDF document text
    • http://szerecsen.hu/editor_up/ninazojefilavivugofev.pdfIn PDF document text
    • https://www.aledrukujemy.pl/ckfinder/userfiles/files/84061976475.pdfIn PDF document text
    • https://carsen.sk/editor_uploads/system/files/regubuvomanejunibitet.pdfIn PDF document text
    • http://uptindia.com/newsimages/file///viwejezolezelabirod.pdfIn PDF document text
    • http://paulgraphics.paulsfashion.in/files/35438953040.pdfIn PDF document text
    • http://pphjako.pl/userfiles/file/tuxogutapu.pdfIn PDF document text
    • https://ipssecurityconsultants.com/ckfinder/userfiles/files/jitazuparofepu.pdfIn PDF document text
    • http://ablerexthailand.com/userfiles/files/limerazetoxebedogopo.pdfIn PDF document text
    • https://cafemocion.com/userfiles/file/62863387601.pdfIn PDF document text
    • http://marklaliberte.com/fckupload/file/82759740474.pdfIn PDF document text
    • https://bhavanarayanaswamy.org/userfiles/file/98221014247.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/sigaz.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/161491dba89d58---loxofiz.pdfIn PDF document text
    • https://uppersanduskyrotary.com/cms/files/File/86336203104.pdfIn PDF document text
    • https://rumputhijau.com/contents/files/64859905115.pdfIn PDF document text
    • http://geologocarmignani.com/userfiles/files/489328095.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/13725653206140413f1a4e5.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_off0000ae2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE2C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c63e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC63E 13872 bytes
SHA-256: c06b141222af7890fbabce75b8851c183b9942cad2e45a3099ffc99cec21dc55
font_02_sfnt_off0000e8c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8C4 10952 bytes
SHA-256: e1af6ae83578a9863f2fd07a34efc8ee65e08892d12d0f5b8cb9c654174dc3ad