Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f6684d4b2884556…

MALICIOUS

PDF

85.0 KB Created: 2021-03-31 23:15:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: a4cdac5b5693b27046cba36dd75821f1 SHA-1: ca181c1f7379b9698d37173b13e1bafd5012b332 SHA-256: 9f6684d4b2884556983415744e5823951f7985d825419ed28c0a7129d137dad3
126 Risk Score

Malware Insights

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

The PDF file contains embedded URLs that redirect to external websites, one of which is identified as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body, though heavily obfuscated, suggests a lure related to programming interview questions to entice users to click the malicious link.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://pelibifir.ru/award?keyword=java+data+structures+and+algorithms+interview+questions+and+answers+pdf PDF link annotation
    • http://milanomoda.site/davoduteg023.pdfIn PDF document text
    • https://cdn.sqhk.co/ruwonumatag/bAgijiR/knights_chronicle_rwby_collab.pdfIn PDF document text
    • http://japadalifu.22web.org/xafogojoxozaxadinagixarer.pdfIn PDF document text
    • https://delimilakemasuj.weebly.com/uploads/1/3/4/4/134400920/7410313.pdfIn PDF document text
    • https://cdn.sqhk.co/benibavagoge/LjgbigB/57646795431.pdfIn PDF document text
    • http://lawekuxidiwote.22web.org/r_programming_certification_udemy.pdfIn PDF document text
    • https://nukevokisoget.weebly.com/uploads/1/3/2/7/132711970/fivexudesozu.pdfIn PDF document text
    • https://kimakinogi.weebly.com/uploads/1/3/0/7/130775446/3137553.pdfIn PDF document text
    • http://1-bog.ru/john_deere_4045_parts_cataloguboiu.pdfIn PDF document text
    • https://cdn.sqhk.co/ramazunor/gcc7Waw/download_game_traffic_fever_racing_mod_apk.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://laxalelowejosi.epizy.com/the_missing_season_1_episode_1_dailymotion.pdfIn PDF document text
    • http://mogavor.epizy.com/79111176310.pdfIn PDF document text
    • http://mapesag.epizy.com/nifapurawuromirabuge.pdfIn PDF document text
    • https://0aed7b51-d02b-4864-a6bb-b478bb809667.filesusr.com/ugd/fbdaab_c0d9695ba37f4aa3acab6a2d19c3eb8b.pdf?index=trueIn PDF document text
    • http://joriboka.epizy.com/kabagexojaxapopev.pdfIn PDF document text
    • https://8994dc82-3839-475c-8de5-8afaa5c13229.filesusr.com/ugd/798b5e_b60bea6145844d91b57137f21922e03d.pdf?index=trueIn PDF document text
    • http://puzegekizizovin.epizy.com/cursive_writing_file.pdfIn PDF document text
    • https://7ef5d8b8-74ac-4e0a-b0a0-fa61ca6462a8.filesusr.com/ugd/23e9be_e086c121b53543618e74e27b594e260b.pdf?index=trueIn PDF document text
    • http://xobikiganerewen.rf.gd/tinovejoguwopuguse.pdfIn PDF document text
    • https://8d67285a-e3c5-4820-bb1a-bb91ce1079a6.filesusr.com/ugd/d54300_1a1e13e84734483fac4125cfb50c01fe.pdf?index=trueIn PDF document text
    • https://d5fd0048-bb8d-45a1-ba21-28d1cb0b7162.filesusr.com/ugd/5e8de6_9472fc3babea4f53a02251cda44c12b5.pdf?index=trueIn PDF document text
    • http://nazonuretowu.epizy.com/apocrifos_de_la_biblia.pdfIn PDF document text
    • http://xadamodovupeniz.rf.gd/ruvigubewozemanepulupud.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_off0000f6e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E3 5836 bytes
SHA-256: f035914ba3c227629b6d0bd642e0fe37c2587e3e40918ed40caf9ba470ee9694
font_01_sfnt_off00010aa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA4 10960 bytes
SHA-256: fc41fca03e62f1e0ac9af5cbb5c53c3c93cb267a2b705c6844a4a621058410cc
font_02_sfnt_off00013021.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13021 16544 bytes
SHA-256: c64f975c7c74378765a15e192890ba001b575443647995d4109c17b56814fb1e