Malicious PDF — malware analysis report

Static analysis result for SHA-256 4851fd9f461ff506…

MALICIOUS

PDF

95.9 KB Created: 2021-04-21 15:50:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: f5990da1cd53af51f6c040c705a6ff90 SHA-1: db74d0c8887b1d88679dbefaa7d2e97118789e8a SHA-256: 4851fd9f461ff506c6e2f833df248cfc19d2a3cb00e1f0d7eb4b06559941e741
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a remote-support lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://leonvi.ru/strik?utm_term=charger+for+ipod+nano+4th+generation PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4443624/normal_60502378f24f7.pdfIn PDF document text
    • http://komunomaled.iblogger.org/delegation_of_authority_and_decentralisation.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417040/normal_605f404e57480.pdfIn PDF document text
    • https://korenumotijele.weebly.com/uploads/1/3/4/6/134687452/93ae2e.pdfIn PDF document text
    • https://sanakifagijegu.weebly.com/uploads/1/3/4/4/134404207/betuxukogosabebo.pdfIn PDF document text
    • https://bugasidajuw.weebly.com/uploads/1/3/1/8/131856032/8045529.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375704/normal_606e3d52d25b5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413976/normal_602402a5d8122.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/e115bd61-20e0-4108-b030-20db2e328431/rumi_bookstore_fremont.pdfIn PDF document text
    • https://s3.amazonaws.com/mukutud/xujovogugalid.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aa8ff6af-4ef8-4408-8a3c-69d999630af0/windows_7_command_prompt_tricks_and_hacks.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/755020e0-38ef-4b30-aee5-8645f5d3368e/jufetotameboreba.pdfIn PDF document text
    • http://lolugedupagimu.epizy.com/background_music_piano.pdfIn PDF document text
    • http://vibamegavisine.rf.gd/kawewulawaxapo.pdfIn PDF document text
    • https://s3.amazonaws.com/bejokazemur/ecosa_bamboo_sheets_review.pdfIn PDF document text
    • https://s3.amazonaws.com/kufazete/baxogejenusixofivudita.pdfIn PDF document text
    • https://s3.amazonaws.com/xipavir/kutogeku.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/64f41fe6-0209-4046-a9ff-a86613edee93/146_or_147_of_the_law_of_property_act_1925.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d68866ca-02af-4d50-9c51-71ee5be922a1/20179913809.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a153f61a-194a-4f0e-ace3-4f0a1c2934c7/4022820900.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/66ef2f9a-5a2b-4099-94cd-43a8e4672b92/33972170726.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/63628183-41e2-42b3-81b7-22e390ee9f2e/14_rejected_books_of_the_bible.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c6ecdae-bf2b-4564-a870-ce33faecb199/our_mathematical_universe_by_max_tegmark.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012c1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C1A 4992 bytes
SHA-256: dd2ea7b7039c440d7a32fdf77a240429bb547aad2fc31f9f36f1e1cba025e720
font_01_sfnt_off00013d17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D17 11568 bytes
SHA-256: 133770620e53eb64461a6f2eeb210e2eef2d1d17f544926e46e10c0786d74178
font_02_sfnt_off00016403.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16403 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378