Malicious PDF — malware analysis report

Static analysis result for SHA-256 88265b650257286c…

MALICIOUS

PDF

78.6 KB Created: 2020-11-19 01:09:36 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 857d5ceb33f29e0b899e408cdb0e1da5 SHA-1: 950a81d147cb0e05dab9a7e03ae59cc18840f1f1 SHA-256: 88265b650257286c750da8846464444305ee69b7682f4d27dde7573280aa70f1
196 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to SEO-optimized PDF download pages, suggesting a link farm or phishing operation. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as a phishing trojan. While no scripts were directly extracted, the PDF structure and embedded links are indicative of a malicious lure designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://traffset.ru/123?utm_term=poc+bible+malayalam+audio+download PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4418370/normal_5fa3b993ea44b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402936/normal_5fafa89f4556d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370540/normal_5f887a3c6222b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403683/normal_5fb59cf77cdb1.pdfIn PDF document text
    • https://kebekeloku.weebly.com/uploads/1/3/4/6/134639455/rudisel.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366035/normal_5f880c0b93329.pdfIn PDF document text
    • https://mowolonob.weebly.com/uploads/1/3/4/8/134874237/lositetof.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385863/normal_5f928410dd0d8.pdfIn PDF document text
    • http://smc.org.in)MeeraRegularMeera2016SMC7.0.0+20171102HussainIn PDF document text
    • http://smc.org.inhttp://smc.org.inIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/lejivugeleguwod/damidegogefixafag.pdfIn PDF document text
    • https://s3.amazonaws.com/paxivogedewilu/98884555727.pdfIn PDF document text
    • https://s3.amazonaws.com/bizamesuwepe/wwe_shield_hd_images_2018.pdfIn PDF document text
    • https://s3.amazonaws.com/lanorolowu/o2_sensor_5_wiring_diagram_subaru.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3ae2d602-ac8f-4ada-9793-53a49474012b/industrial_revolution_study_guide_word_search.pdfIn PDF document text
    • https://s3.amazonaws.com/bajuse/kelogaxifeduv.pdfIn PDF document text
    • https://s3.amazonaws.com/dejazuvorira/extraction_of_benzoic_acid_lab_report_introduction.pdfIn PDF document text
    • https://s3.amazonaws.com/putelekireza/19936516876.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
    • https://gitlab.com/smc/meera/blob/master/COPYINGIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000cd74.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xCD74 18708 bytes
SHA-256: 06a97fc6f46647ec8915ff1067c85818e380fdfdcb7b82f2bcd64c582afd3666
font_00_sfnt_off0000bbfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBFA 5148 bytes
SHA-256: c7e017883610929b8c20dd5a1f24bbd43c7c22ac684a5275e350f4cabdad4e19
font_02_sfnt_off0001063d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1063D 10460 bytes
SHA-256: c798111557dcd4d4cde59fcf7c380b6ba40760381e506ddb8ce4906d75e9e1db