Malicious PDF — malware analysis report

Static analysis result for SHA-256 750c12306954f96e…

MALICIOUS

PDF

72.9 KB Created: 2021-03-23 15:01:21 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 1a58855470461ae7ac201114ed5195a1 SHA-1: 786161aa3432e401e91997a11b88a81b456d7279 SHA-256: 750c12306954f96e7738c8f4ba60558eb4687e2f0f3e8617bcb6486242b1946b
196 Risk Score

Malware Insights

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

The PDF contains numerous external links, many of which are SEO-optimized and redirect to other PDF files, indicating a link farm or phishing attempt. The primary URL, https://maypoin.ru/wix?keyword=biocalculus+calculus+probability+and+statistics+for+the+life+sciences+pdf+download, suggests a lure for a specific book download. ClamAV detection and ML classification confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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.
  • 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://maypoin.ru/wix?keyword=biocalculus+calculus+probability+and+statistics+for+the+life+sciences+pdf+download PDF link annotation
    • https://kotasixunepa.weebly.com/uploads/1/3/0/7/130776076/gimovekegus.pdfIn PDF document text
    • https://cdn.sqhk.co/tajaketo/ghPQgjj/37375465286.pdfIn PDF document text
    • https://kenaveduku.weebly.com/uploads/1/3/0/8/130813649/3102868.pdfIn PDF document text
    • https://dolujutizividev.weebly.com/uploads/1/3/4/8/134864897/7180693.pdfIn PDF document text
    • http://pifopusilegazo.iblogger.org/62645866797.pdfIn PDF document text
    • https://lonofajizol.weebly.com/uploads/1/3/5/3/135389348/gibulak_nodaw_rodorikur.pdfIn PDF document text
    • https://cdn.sqhk.co/woguwubege/jUiefiO/fetopu.pdfIn PDF document text
    • https://wekupadafar.weebly.com/uploads/1/3/5/3/135315244/e6fcb51112.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/bisapovepizaj/best_nimh_rc_car_battery.pdfIn PDF document text
    • https://s3.amazonaws.com/sizabo/87329400192.pdfIn PDF document text
    • http://nusilemil.epizy.com/sakinolutoxufimu.pdfIn PDF document text
    • http://ziradisam.rf.gd/ffs_gaming_report_player.pdfIn PDF document text
    • http://besarod.rf.gd/air_pollution_book_free_download.pdfIn PDF document text
    • https://s3.amazonaws.com/wajufifenoxuj/bloodwitch_susan_dennard.pdfIn PDF document text
    • https://s3.amazonaws.com/dezajok/baana_kaathadi_songs_free_tamilwire.pdfIn PDF document text
    • http://tolerikaduvutef.rf.gd/43371040523.pdfIn PDF document text
    • https://s3.amazonaws.com/fobupojowojon/28848423926.pdfIn PDF document text
    • http://difedomuki.epizy.com/lofimunatotas.pdfIn PDF document text
    • https://s3.amazonaws.com/xuzed/tatuxerosebumapot.pdfIn PDF document text
    • http://kobewanen.rf.gd/android_auto_not_working_on_sync_3.pdfIn PDF document text
    • https://s3.amazonaws.com/lixuzo/kojirotelimokuzerejege.pdfIn PDF document text
    • https://s3.amazonaws.com/xulepiwa/how_to_cook_chicken_tenders_in_air_fryer.pdfIn PDF document text
    • http://xeroxofebamuwu.rf.gd/32520294871.pdfIn PDF document text
    • https://s3.amazonaws.com/biwubeleba/69161440968.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_off0000ddd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD5 5628 bytes
SHA-256: d34b995ecfd7225cccb93097f39438a9fc83ea24802f2a36bb17ab2eb8e6d27d
font_01_sfnt_off0000f103.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF103 10512 bytes
SHA-256: 5ccd2cdc8501bde079d3c126d3b17fe274017ebb2e172da74fe11602fe4ed631