Malicious PDF — malware analysis report

Static analysis result for SHA-256 11fa54b160827d94…

MALICIOUS

PDF

66.4 KB Created: 2021-06-10 17:44:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 55dcce3d66c72106e442d13dd69513bb SHA-1: 68d069830dc607ea042bfe411b869d884da909ed SHA-256: 11fa54b160827d94c2e0d2f8e94f3f808c40228414af7fe97e1dac62fe881299
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious. It contains a large number of external links, many pointing to other PDFs, suggesting a link farm or distribution network. The primary URL, 'https://soxebez.ru/123?utm_term=indefinite+pronouns+worksheet+pdf+6th+grade', indicates a lure related to educational materials, likely to disguise malicious intent. No scripts were extracted, but the PDF structure and numerous external links strongly suggest it's designed to redirect users to potentially harmful content.

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/123?utm_term=indefinite+pronouns+worksheet+pdf+6th+grade
    • https://cdn-cms.f-static.net/uploads/4454302/normal_602e49be6e46e.pdf
    • https://cdn-cms.f-static.net/uploads/4487625/normal_5fd112ed6749a.pdf
    • https://cdn-cms.f-static.net/uploads/4475380/normal_60686b293c763.pdf
    • https://cdn-cms.f-static.net/uploads/4387056/normal_5fdc48f8d9e1f.pdf
    • https://cdn-cms.f-static.net/uploads/4421768/normal_60558ec2b14c6.pdf
    • https://cdn-cms.f-static.net/uploads/4409246/normal_602afdab7030b.pdf
    • https://cdn-cms.f-static.net/uploads/4469827/normal_60586777c7c6e.pdf
    • https://ruzamoga.weebly.com/uploads/1/3/4/7/134761687/c7d3a.pdf
    • https://lotefexikig.weebly.com/uploads/1/3/4/0/134097130/5287b42f69.pdf
    • https://static.s123-cdn-static.com/uploads/4366627/normal_5ffc8e972a2b0.pdf
    • https://cdn-cms.f-static.net/uploads/4370071/normal_60511326351c0.pdf
    • https://static.s123-cdn-static.com/uploads/4385634/normal_5fc979dc8cfd8.pdf
    • https://vegekonewipure.weebly.com/uploads/1/3/5/9/135964828/3285982.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://negovijalulu.pbworks.com/w/file/fetch/144412662/54241097393.pdf
    • https://uploads.strikinglycdn.com/files/a0db96c7-0fce-4adf-8d2e-a7fb7f72e971/21129210806.pdf
    • http://nugewil.pbworks.com/w/file/fetch/144649524/ejemplos_de_suma_o_diferencia_de_cubos_perfectos.pdf
    • https://uploads.strikinglycdn.com/files/ecfd3709-33b9-4dca-909a-302881d35d46/how_to_draw_easy_things_step_by_step.pdf
    • https://uploads.strikinglycdn.com/files/a2b97f68-8966-4cd2-b5b9-b756ee2ba109/tagalog_movies_free_online_streaming.pdf
    • https://uploads.strikinglycdn.com/files/b12d53bf-140a-4301-83fe-9210005dc96e/mabigobotafanofuz.pdf
    • http://wuwolufit.pbworks.com/f/moboduvud.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_off0000c82a.bin
2cbbd1d3bad78c8231a3ce38dc6ff18e72e92463800564c43ca81329df4dc0e9
pdf-font-stream PDF embedded font (sfnt) at offset 0xC82A 5516 bytes
font_01_sfnt_off0000daff.bin
e414c92c2c4d371e992c8f7a96f0b762caee9531a67910ee40082a04cb537d5f
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAFF 9664 bytes