Malicious PDF — malware analysis report

Static analysis result for SHA-256 18135f24e91a5ce7…

MALICIOUS

PDF

104.3 KB Created: 2021-04-01 02:41:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 2fc3821c09e212fff6794cb4cd6887e2 SHA-1: 534740b2bfeb6a96b21cfaebe51b753f434a0f8f SHA-256: 18135f24e91a5ce7d17450b2000f7484eb0ffb4c09509170623f7d9c71358543
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. 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 0.9986

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://maypoin.ru/123?utm_term=digital+aircrew+training+manual+uh+60 PDF link annotation
    • http://widaget.22web.org/bsc_1st_year_chemistry_notes_free_download.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417523/normal_5ff0c313af6e5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4386334/normal_5febc9933b5dc.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384316/normal_60029e0d78dc8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420910/normal_60366ad4db898.pdfIn PDF document text
    • http://copyright-securityx.com/xenakis_metastasis7p9s7.pdfIn PDF document text
    • http://citimart.online/mifavugudikozupupakoloov15p.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374847/normal_6063abada3584.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/b50711f5-4287-44c4-841d-d4eb908d8c01/alpine_ina-w900_bluetooth_firmware_update.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/36a5f857-9a75-43a6-ad8c-68d6e7fdc149/concord_hospital_map_2018.pdfIn PDF document text
    • http://mitikujedusor.epizy.com/alan_gratz_refugee.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/df28c126-7bd6-4d96-be66-f15583a64dc7/life_live_lives_pronunciation.pdfIn PDF document text
    • http://dokubuxopid.rf.gd/afro_house_sample_packs_free.pdfIn PDF document text
    • http://xevezowa.rf.gd/fawemebud.pdfIn PDF document text
    • http://kadekosaraf.epizy.com/cooking_academy_2.pdfIn PDF document text
    • http://kazaxese.epizy.com/bedtime_stories_for_kids_short.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/976bc99e-560c-43b7-b368-78ff552cdf57/tc_renegade_54_cal_loads.pdfIn PDF document text
    • http://bezopebadutaz.rf.gd/47790068901.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7399f14a-832f-4026-a105-5aa7554ddb4b/concordancia_biblica_online_gratis.pdfIn PDF document text
    • https://3c199e1c-ff83-4553-a351-db1e9419129c.filesusr.com/ugd/424a74_8a786310ba084bc68ec39ac3a28f5d8c.pdf?index=trueIn PDF document text
    • https://c0771fee-1ba5-4dbf-bba5-a775c3d44c03.filesusr.com/ugd/544e7e_d606d50e5c0a460fbcd2748ddb2396f5.pdf?index=trueIn PDF document text
    • http://rututovabin.rf.gd/zoe_happy_fit_guide_free.pdfIn PDF document text
    • http://xeminujuri.epizy.com/snow_report_angel_fire_new_mexico.pdfIn PDF document text
    • https://8c4778c4-ed17-4cf1-86f9-5448e21c5c15.filesusr.com/ugd/6da380_4ad88acd97f34a8eaacca9b66e06281d.pdf?index=trueIn PDF document text
    • http://xorikija.epizy.com/beniwarib.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_off00014477.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14477 5424 bytes
SHA-256: 243cf36dfe3a0362523b414ba3050483713b4051958c660a07fa699b773803ff
font_01_sfnt_off000156da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156DA 11416 bytes
SHA-256: 2ba716050299a407613cd2c1142c5885b53d03689a1082b41ea0bb1c6fe1f719
font_02_sfnt_off00017dc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17DC9 16204 bytes
SHA-256: 532315dfdc59b350d447ad91845dd8cc72a836e684f536ab9a4305dc5b53fb8e