Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5bc5320d6825441…

MALICIOUS

PDF

78.7 KB Created: 2021-03-28 01:21:16 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 331e830107ef87aa6046498887aaa0c9 SHA-1: 263d4742258b7d6a48079a51d8eaf6b8b306b5bb SHA-256: d5bc5320d6825441d50759a2658cba599c0234c6db45116eefd71ce07b5c326a
146 Risk Score

Malware Insights

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

The PDF contains malformed streams and is flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It includes numerous URLs, one of which is a link farm designed to redirect users to potentially malicious content, and another points to a PDF hosted on disposable infrastructure. The document body, though heavily obfuscated, appears to contain text related to academic topics, likely as a lure.

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://fokemale.ru/strik?utm_term=evaluate+noam+chomsky+theory+of+language+development PDF link annotation
    • http://poradoit2.site/find_my_friends_not_showing_distanceqf114.pdfIn PDF document text
    • https://wiwamimojuwat.weebly.com/uploads/1/3/0/8/130813692/mozudadatunasam-korewuwulima.pdfIn PDF document text
    • http://pihodze.com/93730640392ko4zy.pdfIn PDF document text
    • https://pexegiwu.weebly.com/uploads/1/3/4/5/134526087/fasisokegu.pdfIn PDF document text
    • http://constructionhouse.info/psycho_robert_bloch_movie29k9b.pdfIn PDF document text
    • https://zafigitelerom.weebly.com/uploads/1/3/4/3/134338481/rudozeduwakagax.pdfIn PDF document text
    • http://nubolutlion.xyz/suzafakutepofazarasufoda79yew.pdfIn PDF document text
    • http://vivofuma.66ghz.com/33538723240.pdfIn PDF document text
    • http://iuts.space/45049528771c9j5d.pdfIn PDF document text
    • https://zizusufake.weebly.com/uploads/1/3/4/6/134646877/munivujixuxo-porozoki-muwugetomaxun-manugifugego.pdfIn PDF document text
    • http://usesol.xyz/6790223314f2r0k.pdfIn PDF document text
    • http://verifiedbadge-lnstagram.com/simile_and_metaphor_lesson_plan_4th_grade07uyh.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wotalajo.epizy.com/editing_to_word_document.pdfIn PDF document text
    • https://s3.amazonaws.com/rikolesafuwofar/fleck_5600_econominder_parts.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/85e26dab-a155-4dc4-93fc-5110c951a2ae/how_to_develop_android_apps_using_python.pdfIn PDF document text
    • https://s3.amazonaws.com/jajuzasalikirut/the_yellow_wallpaper_text_dependent_questions_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4ec92088-720a-4d49-a95d-55977fb42d49/fulukoru.pdfIn PDF document text
    • http://labutebumir.rf.gd/how_to_send_mail_to_northern_ireland.pdfIn PDF document text
    • http://jojudodadanu.epizy.com/why_does_hp_officejet_pro_8600_offline.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7bb61bf0-09f6-4f0e-82c4-83099d9d57ae/how_to_get_to_firmament_ffxiv.pdfIn PDF document text
    • https://s3.amazonaws.com/toliwudalamem/sat_practice_test_4_curve.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b8a4cebc-185c-48d1-83e8-5841841cd281/42003216010.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f62df20e-45fe-48f9-aaa5-80ecbfd7d276/sixunubukapi.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f38f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF38F 5752 bytes
SHA-256: a1c5eb4a1208dec2e03186b813061609c4a8af33e4141e829718069a4808f3aa
font_01_sfnt_off00010713.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10713 10660 bytes
SHA-256: bca5a6fdff4aaf25206f678de36cd4ac9f460fe1c582fe29e8250e8adfaf955a