Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c57fcf7bba1ab95…

MALICIOUS

PDF

74.6 KB Created: 2021-03-15 17:41:43 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 35edb8c2c240ce54cba3d1d999400213 SHA-1: b2955950226710dc7cf5163fdc16b1c8dd427027 SHA-256: 2c57fcf7bba1ab95ba2e34404e05b8344abfc3f247a412d8f321daa7a002a8c0
136 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to SEO-optimized PDF files, a common tactic for link farms and phishing. The heuristic 'PDF_SEO_LINK_FARM' indicates a large number of external links, and 'PDF_SEO_UTM_REDIRECTOR_LINK' specifically flags a redirector URL, suggesting a malicious intent to redirect users to potentially harmful sites. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://jottigo.ru/strik?utm_term=preposition+song+lyrics+jingle+bells PDF link annotation
    • http://good-production18.site/79504476009b1bdy.pdfIn PDF document text
    • http://helps-lnstagramcopyrights-about.com/btec_level_3_engineering_unit_6_answers13po9.pdfIn PDF document text
    • http://detonic-hypertonie.website/foxit_reader_for_ubuntu_freebxxb8.pdfIn PDF document text
    • http://rigoditibalun.mywebcommunity.org/70506210346.pdfIn PDF document text
    • http://relax35.ru/pidole39iff.pdfIn PDF document text
    • http://zofazosedam.iblogger.org/how_to_turn_casio_watch_alarm_off.pdfIn PDF document text
    • http://kulanefimolon.mypressonline.com/book_meditations_by_marcus_aurelius.pdfIn PDF document text
    • http://tivoraxureb.22web.org/nuridenef.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://doriponesarom.myartsonline.com/charting_oxidation_number_worksheet_answers.pdfIn PDF document text
    • https://s3.amazonaws.com/voxipanovigepiv/54257865886.pdfIn PDF document text
    • https://s3.amazonaws.com/veraxawewib/bebepibofokew.pdfIn PDF document text
    • http://zilowovuv.atwebpages.com/economist_style_guide_2020.pdfIn PDF document text
    • https://s3.amazonaws.com/mutirexa/instagram_followers_apk_2019.pdfIn PDF document text
    • https://154530d8-637b-49d0-b90a-43bf07a176fb.filesusr.com/ugd/59359a_a26448e36321463cb17cf60bad765bd6.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/bulozor/present_continuous_tense_worksheet_for_grade_6.pdfIn PDF document text
    • http://vuribokuz.epizy.com/tobefozazofugi.pdfIn PDF document text
    • https://0a497e50-07dd-462d-832d-d8678f741a8e.filesusr.com/ugd/5f857b_a740bb1c881b4345a385d192b011504e.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nefomojuwet/6578180806.pdfIn PDF document text
    • http://figavexujofivu.rf.gd/6th_grade_math_slope_worksheets.pdfIn PDF document text
    • http://pezedavepajizum.rf.gd/atlas_copco_compressor_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/figidireki/causative_verbs_list.pdfIn PDF document text
    • https://8eefcaf3-52f5-4123-8be5-b1f0aaeea45e.filesusr.com/ugd/1d3654_6d9bf0a0fd3c40508a658af8afdc695c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mexijegedakol/illness_word_search_worksheet.pdfIn PDF document text
    • https://76ed6b59-b034-43ac-b949-e1c08f76e3cb.filesusr.com/ugd/ee6100_0ad5394fdfdd4ba29a492cb9472f61d0.pdf?index=trueIn 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_off0000e5ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5EF 5208 bytes
SHA-256: f312ed880106147d905a508df02ae298e876ce096785669354626215975ba9e2
font_01_sfnt_off0000f7c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C6 10976 bytes
SHA-256: eb14a83d791ff1207c232ae2fc79855551eec9307849d4b0611788590d03cb2f