Malicious PDF — malware analysis report

Static analysis result for SHA-256 b957be7dbcb8fc1a…

MALICIOUS

PDF

81.4 KB Created: 2021-05-12 10:08:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6c43ed4252dc3356254e249d538ba43e SHA-1: 3ec26f47dc621b3549cea95b1f9de4331e474195 SHA-256: b957be7dbcb8fc1a969aedd8c1d819d51a59d13a1bd3fae27d9227ea405080ad
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous distinct hosts, many of which are compromised WordPress installations. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to manipulate search engine results or redirect users to malicious content hosted on these compromised sites. No scripts were extracted, and the document body was heavily obfuscated.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/4a43e26714f7a7b03cd672c508e27221/55552103041.pdf
    • http://bielwod.com/userfiles/file/dirakisezumuxijol.pdf
    • http://curry-box-deluxe.de/userfiles/file/rujupakeruvameduna.pdf
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/2427e5b25b144dabbf04c2d1bd129aa0/sufakokedavo.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16085035301ff6---77725876104.pdf
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd7c498b99---busikivotugajusoborux.pdf
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/abb8c884d89140256ea4f97c3162b6da/vifenozi.pdf
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/790pnp4a8g7q46t9re0irmg9g7/zosudinude.pdf
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/c7dba82183c94fd4fdc5142c3970aba0/95999155858.pdf
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/76bbd2b66bed76224c07a6a097a99004/felitibiwafew.pdf
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/843972e3b9e101b522790b52cdc305b7/18014187125.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/ru2jiftq436nq213iule5aurac/45218086498.pdf
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/8fmp3nbhp8sdbtm2diot606qkd/kemavoketovofupilixeza.pdf
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1606c90987cee9---nevupe.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608dfa9fb5944---90893047313.pdf
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/ndkstb9dvgmvmdbngdrlr1k7kq/21076492236.pdf
    • https://designcoordinators.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076031d85be6---49185530763.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=greedy+cave+guide+skill+build
    • 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://scripts.sil.org/OFL

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e70d.bin
3ae36df60cb821bc64c029736f04f76dee71b6709a9207cbcbc492132cd18c74
pdf-font-stream PDF embedded font (sfnt) at offset 0xE70D 3140 bytes
font_01_sfnt_off0000f247.bin
0c3a4fc4c9ec5262b92b0054525878c2a4482698ecda39eef3ba4f87a001ac5a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF247 5088 bytes
font_02_sfnt_off000103b7.bin
8125a41bd2e0642c05a9c88a43a65894043d5d88ea6bef20e5a2cab50f23d4f2
pdf-font-stream PDF embedded font (sfnt) at offset 0x103B7 11240 bytes
font_03_sfnt_off00012a2f.bin
4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A2F 4324 bytes