Malicious PDF — malware analysis report

Static analysis result for SHA-256 25acd6fcda073f11…

MALICIOUS

PDF

77.5 KB Created: 2021-04-03 19:02:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: a97fb27791238b20838e5f01ab4b433c SHA-1: 84183ffa6b00e3791a598aa733056ee45702cb6b SHA-256: 25acd6fcda073f118b506725fa8682e2b57b409dab6646b63d5fb6304b2e752c
126 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting services, indicating a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the presence of numerous external URLs, including one with a suspicious query parameter, suggests a potential for distributing further malicious content or leading users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://jacksth.ru/award?keyword=attachment+style+quiz+pdf PDF link annotation
    • http://4kuhd.me/vidas_secas_resumenj6c1n.pdfIn PDF document text
    • http://rentline.pro/yes_please_meals7kkka.pdfIn PDF document text
    • http://betmoy54.com/buzanafunebitiwo8xvgy.pdfIn PDF document text
    • http://wikatugakuvifi.iblogger.org/18535513975.pdfIn PDF document text
    • http://runmasten.online/habit_7_sharpen_the_saw_activitiesa5njj.pdfIn PDF document text
    • http://verification-help.business/porakoxobipuromip41j19.pdfIn PDF document text
    • http://mopexaxurip.getenjoyment.net/63880494027.pdfIn PDF document text
    • http://lixorajepidil.mygamesonline.org/dulenenumitizirorex.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://dc010c70-835d-4b56-8cb0-1e1bda7cab64.filesusr.com/ugd/fb576b_10bd2e7b466044c19373ccbb8467f244.pdf?index=trueIn PDF document text
    • https://51956041-da35-40aa-96c1-085c1f47c80d.filesusr.com/ugd/e6e573_dd77e3dadac343d8abfebc2f0a672f9f.pdf?index=trueIn PDF document text
    • http://tosodesuvivat.epizy.com/andratx_android_apk.pdfIn PDF document text
    • https://55d63786-14d6-44de-84d0-33f1fb383c44.filesusr.com/ugd/45fd81_baca365c3cc94fbc935c4e07cc042815.pdf?index=trueIn PDF document text
    • http://benapubusepem.rf.gd/95729710868.pdfIn PDF document text
    • https://9d50af6f-dbf7-41ba-b854-83985329a12b.filesusr.com/ugd/33c377_e6b9c270599247eb9871108fd036115e.pdf?index=trueIn PDF document text
    • https://8569cc17-8b2a-4187-ace0-95b0550b99f0.filesusr.com/ugd/d6eede_4707f7cdcbb6426cb4496e9700accf68.pdf?index=trueIn PDF document text
    • https://6b54b0b2-91db-43cc-88c8-bbc4f7e20b37.filesusr.com/ugd/a773aa_2d3a58d775504c4ca4ded8d2b2053a0e.pdf?index=trueIn PDF document text
    • https://49432a94-54bc-4d13-9d12-ea41d731e1b8.filesusr.com/ugd/a7c689_f230c1e4e0a1469492cf3f704ca86119.pdf?index=trueIn PDF document text
    • https://a0f88182-e1f9-4a9c-ba22-d5ce004c6985.filesusr.com/ugd/2f3216_595c003bfa014d31bd7cc0b056612b29.pdf?index=trueIn PDF document text
    • https://fb4bdcd3-28a3-4206-a6c3-fb267f511c23.filesusr.com/ugd/0ad562_73bebb5e707540548806cf8911eea9ae.pdf?index=trueIn PDF document text
    • https://989244f3-426d-4557-b4f1-0018dac9047c.filesusr.com/ugd/57c819_42c41f26af1a48e09d15129c13a6adf8.pdf?index=trueIn PDF document text
    • https://5ce19dfa-329f-495d-88d1-e1e7834d9072.filesusr.com/ugd/d902bb_46c7410f3e274a3ab159a60d8de424a9.pdf?index=trueIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f072.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF072 5568 bytes
SHA-256: bb48d4a93c2d687550b90ef0ca3c6aaa57cddb427b4634ae3822385d99f51bb2
font_01_sfnt_off00010353.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10353 11088 bytes
SHA-256: 5fa10e1def614c80ba11637a03383ac7c48088c8f9ef588f01714bec6cef8342