Malicious PDF — malware analysis report

Static analysis result for SHA-256 43c25d0bcc40e336…

MALICIOUS

PDF

87.5 KB Created: 2021-09-11 08:58:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: fde60a0e3995211c613a5ac40fe8bdc0 SHA-1: a897df374395a17a0ae623a57846589a1600f7f4 SHA-256: 43c25d0bcc40e336fa6784ea1a8d3b23b32f7a84fc2d51e33a943da4283a5cbb
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external resources, with a high-confidence heuristic identifying a link to an algorithmically-generated URL on potentially disposable hosting. ClamAV detection and ML classification strongly indicate maliciousness, specifically flagging it as a phishing trojan. The presence of embedded URLs and the nature of the heuristics suggest a phishing or scam attempt designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 http://4rrecycle.com/files/file/40281948653.pdf In PDF document text
    • http://ms-krmelin.cz/app/webroot/files/files/nadevedabororowejuko.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/meruwogisojeniwiwifuk.pdfIn PDF document text
    • http://bilmatbasim.com/userfiles/file/24217926686.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/bezapiw.pdfIn PDF document text
    • http://swancentive.com/cote_dor_import/admin/ckfinder/userfiles/files/16994665093.pdfIn PDF document text
    • http://abakus-routing.co.uk/ckfinder/userfiles/files/rikarirofipo.pdfIn PDF document text
    • https://ptkas.com/kingkong/userfiles/files/beturiretal.pdfIn PDF document text
    • http://abpjseah.news-read.com/upload/files/64233900042.pdfIn PDF document text
    • http://bitree.net/ckfinder/userfiles/files/86227238454.pdfIn PDF document text
    • http://sictombbi.fr/ckfinder/userfiles/files/gapedafotegoxalesekesaba.pdfIn PDF document text
    • http://xn--k1akb4c.xn--p1ai/userfiles/file/60271491751.pdfIn PDF document text
    • http://bonezi.morefriendship.com/upload/files/56361098175.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/44618322738.pdfIn PDF document text
    • http://sakem.org/userfiles/files/kurujezezadusibo.pdfIn PDF document text
    • https://nangluongvada.com/uploads/files/20067773765.pdfIn PDF document text
    • http://borik.customreal.sk/data/files/77382281218.pdfIn PDF document text
    • https://superiorservicesandsolutionsfl.com/nbloom/fckuploads/file/49085666904.pdfIn PDF document text
    • http://hoanhaochemical.com/uploads/files/vakizuxetixej.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/36355661696.pdfIn PDF document text
    • http://xn--80aafjbawrcdgsodbdciig4a5v.xn--p1ai/pict/file/93283113873.pdfIn PDF document text
    • http://andrenickels.de/ckfinder/userfiles/files/letaxezegewaxisugikug.pdfIn PDF document text
    • https://limberhurstgallery.com/imageuploads/file/titixe.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/aniposawu.pdfIn PDF document text
    • http://baheth24aqari.com/ckfinder/userfiles/files/ruposi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=best+paid+wallpaper+app+for+androidPDF 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_off0000f1ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000109c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109C4 10632 bytes
SHA-256: 6c5af31ea5391d4a21c7a8cf839caf94ab9623557452fb4bfe40ec3251a5edb1
font_02_sfnt_off0001224f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1224F 17772 bytes
SHA-256: d01212fb42dcd9dc02993fe40ccc3c8db0e790a9adab51aa250731d9af150adf