Malicious PDF — malware analysis report

Static analysis result for SHA-256 918b9d54c5f4b314…

MALICIOUS

PDF

79.5 KB Created: 2021-03-30 23:56:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: a1959610202c95142bc62685cb6886ae SHA-1: 25eead30b4837912a153b211b6f18a2161664efb SHA-256: 918b9d54c5f4b314e8988ec154edf1e60a2d59a3b3c89d197a5d509634fc2c91
216 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The sample is a PDF file flagged by multiple heuristics as malicious, including brand impersonation for credential phishing (INSTAGRAM) and a large number of external links, suggesting a link farm or SEO poisoning attempt. The ML classifier and ClamAV detection further support its malicious nature. The embedded URLs likely lead to further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • 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 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.
  • Brand-impersonation credential phishing lure critical SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: action link to abused redirector https://gosesubamumu.weebly.com/uploads/1/3/5/3/135348433/nufawapimalurovakemu.pdf.
  • 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://fokemale.ru/award?keyword=advanced+computer+architecture+notes+for+cse+7th+sem+pdf PDF link annotation
    • http://detozube.scienceontheweb.net/chokher_bali_story_in_english.pdfIn PDF document text
    • https://gosesubamumu.weebly.com/uploads/1/3/5/3/135348433/nufawapimalurovakemu.pdfIn PDF document text
    • http://piwofoterif.sportsontheweb.net/daily_english_speaking_practice.pdfIn PDF document text
    • http://vexizudu.medianewsonline.com/fuzoda.pdfIn PDF document text
    • http://fonudesuwobulud.mygamesonline.org/bazabazofunu.pdfIn PDF document text
    • https://tiralilibixadu.weebly.com/uploads/1/3/4/5/134500138/sewegosoxubide.pdfIn PDF document text
    • https://ziziwatir.weebly.com/uploads/1/3/4/7/134713039/2763897.pdfIn PDF document text
    • https://kavosoxevab.weebly.com/uploads/1/3/0/8/130874108/jazoridow_bogor_fimuganemer.pdfIn PDF document text
    • http://xepuxesadara.mypressonline.com/positive_emotions_list.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/pisik/spectrum_tv_guide_mentor_ohio.pdfIn PDF document text
    • https://s3.amazonaws.com/dobesogum/git_command_to_list_all_local_and_remote_branches_of_a_repository.pdfIn PDF document text
    • https://s3.amazonaws.com/ganubifirigevi/2473186974.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bb9787cc-d6ee-4c52-b76d-af20a450e8f3/zowanik.pdfIn PDF document text
    • https://s3.amazonaws.com/siwixomudit/dyslipidemia_guidelines_2015.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ac1a25a5-c2cf-43e1-b31d-96732deb6abc/19416304905.pdfIn PDF document text
    • https://s3.amazonaws.com/mevuzokekenojab/57499636978.pdfIn PDF document text
    • https://s3.amazonaws.com/minaxigevani/super_system_2_magyar.pdfIn PDF document text
    • https://s3.amazonaws.com/fokapikow/animation_in_android_arsenal.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4e341c6b-95af-4e5b-88e9-3d63a453f121/which_of_these_events_occurred_most_recently_in_the_history_of_earth.pdfIn PDF document text
    • https://s3.amazonaws.com/xuxifuzituwu/boxuri.pdfIn PDF document text
    • https://s3.amazonaws.com/bopuxosavubare/best_paid_android_apps_reddit_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c95c34b5-9adb-4a11-9490-c25bdb18d904/gokerexodanuweruzofavu.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_off0000e2f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2F0 5492 bytes
SHA-256: 4ec62c13bbfe910276aa2e7dc32578b6c21dfc4a4b458483896d58c134d1976a
font_01_sfnt_off0000f581.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF581 10732 bytes
SHA-256: 151bb32795920d17e234c4cfa5ad74e0e9d8860ef95b49be619a586e5619fa42
font_02_sfnt_off00011a53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A53 16096 bytes
SHA-256: 3311b17ee2c875cbe6cbffb6f03bc8dc0cda13b56d5eae708f8f8ecc9c9ca689