Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9d8b3801b069df9…

MALICIOUS

PDF

71.9 KB Created: 2021-09-15 10:13:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 339afb07e43f1f88cd873dc95b29e685 SHA-1: 2e58376f63eb974192d0c4d62e6fd5c2deb2f892 SHA-256: f9d8b3801b069df9695bb596b4c37b6cb8b0ea4f6dc39d67a440795bf310c5ce
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a PDF link farm pointing to compromised WordPress upload storage, suggesting a phishing or redirection scheme. The presence of numerous URLs, many hosted on potentially compromised sites, reinforces the attack pattern of directing users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b179786ed5---xinelunemigufadepamebam.pdf
    • http://jewelry-shopping-city.com/uploads/files/202109051113253453.pdf
    • http://newworldss.com/uploads/file/99394677839.pdf
    • http://miryangpension.com/FileData/ckfinder/files/20210909_62544A532A471954.pdf
    • http://ccsup.co.th/uploads/ckfinder/files/dufutilimekax.pdf
    • http://wsp.pl/userfiles/file/9937850356.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16134ce4155a07---9783711609.pdf
    • http://arisutour.com/ckupload/files/xixegurosiseveg.pdf
    • http://daltan.hu/userfiles/file/82932714022.pdf
    • http://merwepizza.com/upload/file/96882363476.pdf
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161417abd06f24---81932252339.pdf
    • http://teplo76.ru/uploads/file/dexupogulasemiwigiro.pdf
    • https://madhubanindiancuisine.com/nbloom/fckuploads/file/57915256520.pdf
    • http://papierplus.pl/userfiles/file/vegipalatalomovudoludo.pdf
    • http://dasbluemchen.com/rolatukuwari.pdf
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161411094e3616---14004659444.pdf
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/65d978495e46cd6cea5747d0a6f6ac29/jutepejijuwulikoneju.pdf
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/161416d5e43903---94599931836.pdf
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/161416d0f435e4---62129955828.pdf
    • http://dsraxys.com/uploads/40623938330.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614113ed73438---96415775602.pdf
    • http://yigang-lin.com/uploads/files/202109120621282139.pdf
    • https://cauthinh.com/luutru/files/51848387215.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=how+open+applock+password
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b8b0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8B0 16792 bytes
font_01_sfnt_off0000d0c2.bin
e6811b92c3cc2e28fc5eaeb962a81315c01badd6b7b6c16d03361f55bcef1e65
pdf-font-stream PDF embedded font (sfnt) at offset 0xD0C2 16424 bytes
font_02_sfnt_off0000fa1e.bin
d2b78e0bc045a5b3edb199d5da1f15b14d14f94b07566b2676cea414027739ca
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA1E 10484 bytes