Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a9c669c1425526e…

MALICIOUS

PDF

96.9 KB Created: 2021-03-25 06:34:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 72a41856979c1fdb032fec5a593100ec SHA-1: 21f9c715b1558329b687d6d2865421189d18dbe3 SHA-256: 1a9c669c1425526ecb8653a1c8ce118b3869c912e305db82595c4cb9c3b170ff
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a large number of external links, identified as a link farm. Several heuristics indicate this is a malicious SEO link farm, with some links pointing to disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to distribute further malware or engage in phishing. No scripts were extracted, but the PDF structure itself is indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 6

  • 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.
  • 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://nipisod.ru/award?keyword=numerical+modelling+of+failure+in+advanced+composite+materials+pdf PDF link annotation
    • http://swiss-gear.store/215807241971tjt7.pdfIn PDF document text
    • http://ses-sanobrabotka.ru/the_17_indisputable_laws_of_teamwork_john_maxwellhcgce.pdfIn PDF document text
    • http://suwufexez.sportsontheweb.net/best_way_to_speak_english_fluently.pdfIn PDF document text
    • http://matawobedopikam.mywebcommunity.org/jekuxurekavijiwozuwav.pdfIn PDF document text
    • http://lidlid.xyz/witcher_3_eternal_fire5ds2h.pdfIn PDF document text
    • http://pitikudefojeken.getenjoyment.net/83727126175.pdfIn PDF document text
    • http://tevfikyuce.xyz/lakshmi_ashtothram_lyrics4917k.pdfIn PDF document text
    • http://remontvorot24.com/fexiwidezelivoxanep179uv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://9610c43f-1b2a-4a8a-b660-75aaf3908198.filesusr.com/ugd/286fb8_27bc60c3c0c0487684fa90fc81923cc4.pdf?index=trueIn PDF document text
    • https://ab2ac9d4-4772-4872-829d-c19fde0a4f90.filesusr.com/ugd/b919b3_e9c8e27e75d7459f9dfb8b4de8917566.pdf?index=trueIn PDF document text
    • https://eaae50f7-3b1c-4f1b-9b3c-e2a48377569d.filesusr.com/ugd/b96e41_82c0487379f54a8b86d0cd6c3931b534.pdf?index=trueIn PDF document text
    • http://xudadadof.epizy.com/7388464695.pdfIn PDF document text
    • https://s3.amazonaws.com/fatikonavori/17093082983.pdfIn PDF document text
    • http://tuvajitivozozek.rf.gd/zefuvuv.pdfIn PDF document text
    • https://s3.amazonaws.com/nokiva/platform_bed_frame_solid_wood.pdfIn PDF document text
    • http://molodoku.rf.gd/duloguruwifezinovinixari.pdfIn PDF document text
    • https://s3.amazonaws.com/wemupajese/mineral_water_bottle_manufacturing_process.pdfIn PDF document text
    • https://ba428ff1-d53d-4eb5-bdb2-cc960067f420.filesusr.com/ugd/7041e4_fa6cc2f9ff8a41b29dfbe1aeaf4e3852.pdf?index=trueIn PDF document text
    • https://fccd5518-64e1-462d-9dbe-8d8d8a19ca7a.filesusr.com/ugd/eb005d_97839088f691493fa2142fba840d319e.pdf?index=trueIn PDF document text
    • https://e6b56e3c-1b88-4cfb-972d-ab1702b0a06e.filesusr.com/ugd/8c0e65_e667e6acf5ea4ea492f6d82b92f18aa1.pdf?index=trueIn PDF document text
    • https://dc6b22d1-fd3c-476a-b8f1-b0505981f591.filesusr.com/ugd/ab5adf_42f8cbf422cb4fc999bd6d12413e1a89.pdf?index=trueIn PDF document text
    • http://joxelugokolutu.rf.gd/kozafax.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
    • 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_off00011fef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FEF 5504 bytes
SHA-256: 4d0699bfd625b646bd6d3b23c8029c38b2a2d8407698270362335e1fb72e30bd
font_01_sfnt_off000132a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132A7 12348 bytes
SHA-256: 811340a4d24442f4a3add1972dd0128a091079a344f037d0e596d6c00c2ff3ae
font_02_sfnt_off00015b94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B94 16904 bytes
SHA-256: a8d693a1c61e4b0b8c85df4395d3c65a1f5e6457a37c0399bfae976cbb7587e5