Malicious PDF — malware analysis report

Static analysis result for SHA-256 21ad1ed21689714d…

MALICIOUS

PDF

87.7 KB Created: 2021-04-14 11:51:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: bb5b3b25f0e9e76efb65fb42f909613e SHA-1: 2376b0bac898a96add2f89a24fa12f6f59ef133b SHA-256: 21ad1ed21689714d36963f9a06f70c59cfb83c30c132c2ae266645b82d7f696a
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were extracted, the sheer volume of suspicious URLs and the heuristic firings point towards a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • 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://soxebez.ru/strik?utm_term=how+many+calories+in+a+sonic+hamburger+bun PDF link annotation
    • http://eushopvmn.site/vscode_markdown_plantumlohrls.pdfIn PDF document text
    • https://gemajoxow.weebly.com/uploads/1/3/4/7/134721961/185c00.pdfIn PDF document text
    • http://niluwipewuxasa.medianewsonline.com/baxunovogidubekigizo.pdfIn PDF document text
    • http://zusiwibewire.mypressonline.com/author_s_purpose_worksheet_5.pdfIn PDF document text
    • http://mufosubofamar.mywebcommunity.org/rrb_bank_syllabus_download.pdfIn PDF document text
    • http://help-feedback-amzn6.xyz/37527441067j146o.pdfIn PDF document text
    • https://rijagadufe.weebly.com/uploads/1/3/1/6/131606992/1613178.pdfIn PDF document text
    • http://instapriz24.site/asma_ul_husna_arabicinion.pdfIn PDF document text
    • https://pudodogefelareb.weebly.com/uploads/1/3/1/6/131606347/b1b2cd3e9b32.pdfIn PDF document text
    • http://jonebosu.mywebcommunity.org/pifewijenasaru.pdfIn PDF document text
    • https://nimekeboxiz.weebly.com/uploads/1/3/0/8/130873861/6874b1f989.pdfIn PDF document text
    • http://xufededubumavif.scienceontheweb.net/how_to_extend_eaton_fuller_shifter.pdfIn PDF document text
    • https://neverazu.weebly.com/uploads/1/3/4/9/134901342/8586454.pdfIn PDF document text
    • http://komarovskii.xyz/how_long_do_recaro_car_seats_lasts7byl.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://f8206d31-21c4-4aef-9da9-e4259ded718a.filesusr.com/ugd/c2bdac_aebb91d0a48a47a9b8180edb1ef397b3.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/timeziso/guided_math_workshop_2018.pdfIn PDF document text
    • https://s3.amazonaws.com/bogijexu/web_banner_design_psd_free.pdfIn PDF document text
    • https://s3.amazonaws.com/savifin/79232138487.pdfIn PDF document text
    • https://e192e36c-395d-4660-9df6-aa7aed00c30a.filesusr.com/ugd/3aee12_f00526eb92124e0281512b99bdb932a1.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/sugowubuf/xewomil.pdfIn PDF document text
    • https://6f1239e7-da96-47bf-8adb-22d47a96a9da.filesusr.com/ugd/bb5a15_934596ef13f4465a9739d989462d090f.pdf?index=trueIn PDF document text
    • https://746420f6-3007-491b-ba72-fd43be5094e5.filesusr.com/ugd/277b62_1ea623fbce4042d6b212878d7d45f470.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_off00011554.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11554 5508 bytes
SHA-256: 0162994b14c822250589fc8941bd2eba32921beb868cc1fb793fe5fe7e31c283
font_01_sfnt_off000127f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127F7 12484 bytes
SHA-256: 1783dc5becbbeae4a042442daca2062d7c0f6312c26c2e3dd8c71f65c4a6dbbc