Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b20367ac264861f…

MALICIOUS

PDF

71.6 KB Created: 2021-04-04 14:57:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 4fac7a8f8255c38781dd2e17721d0afd SHA-1: 5efb4defd1de36b09a61fead04036cdfb301ffe5 SHA-256: 1b20367ac264861f8d53e30180b1d95bf8e7ed344e73dbc0ae2f7f0f2ac84a6b
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, with a primary URL pointing to a suspicious domain, likely part of a link farm or phishing scheme. The document body, though heavily obfuscated, suggests a lure related to educational materials to trick users into visiting the malicious URL.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://soxebez.ru/award?keyword=adjectives+worksheet+3rd+grade+pdf
    • https://xudibonazo.weebly.com/uploads/1/3/4/3/134353284/2631979.pdf
    • https://cdn.sqhk.co/ramazunor/hDgqFgc/furniture_mod_for_minecraft_pc_1._7._10.pdf
    • https://menedufigejit.weebly.com/uploads/1/3/1/4/131482930/2921301.pdf
    • https://cdn.sqhk.co/duxadikoti/aPkibQq/spinal_tap_11.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://e60c805d-b9e1-47fc-b045-983511e9ac1f.filesusr.com/ugd/116bb2_432761d30eb0487c878cc9d66970d7e6.pdf?index=true
    • https://10bc5e17-7652-4c7e-9b43-999b3eb3b021.filesusr.com/ugd/5edc69_88087f64df0c449198245384e5a34dc2.pdf?index=true
    • https://s3.amazonaws.com/kavalukato/cuddle_buddy_application_form_blank.pdf
    • https://77abcf6a-1f47-4233-a5f7-28832101be0a.filesusr.com/ugd/e29e5c_ca298b5175b744fa903e012330448360.pdf?index=true
    • https://s3.amazonaws.com/nowonovege/12520824961.pdf
    • https://s3.amazonaws.com/dutimajizowa/teori_marxis.pdf
    • https://s3.amazonaws.com/norozovijalu/pimefunutirurit.pdf
    • https://s3.amazonaws.com/mujesogi/rca_surround_sound.pdf
    • https://s3.amazonaws.com/fifuto/best_games_for_android_offline_under_100mb.pdf
    • https://s3.amazonaws.com/wovisak/98786889258.pdf
    • https://s3.amazonaws.com/gelawiweza/edesign_curriculum_lesson_5_answer_key.pdf
    • https://s3.amazonaws.com/wupixufekijax/nipisitimipumol.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8af.bin
b0520694354d646234bff444703ad299ed3996f95bfa2e8f2f257d5f3ed2d424
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8AF 5832 bytes
font_01_sfnt_off0000eca2.bin
3b428a249b08a42cfbb9e3ccbd7aea8c04bfa2e6ed72bb433347cb53cd1852a5
pdf-font-stream PDF embedded font (sfnt) at offset 0xECA2 10640 bytes