Malicious PDF — malware analysis report

Static analysis result for SHA-256 91e9de9cb34e348d…

MALICIOUS

PDF

78.0 KB Created: 2021-03-17 00:30:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: ad936a0c29aade7b9b0d5187620d43b4 SHA-1: d3d97b60981a9fd6a39b3b1dd20f54d6b3dfe243 SHA-256: 91e9de9cb34e348d5b12bb2ca512c198aa3999ee4c35e2ead9659266022c824a
144 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF document employs SEO link farming and redirector techniques to masquerade as a download for 'apk super mario bros 2'. The primary malicious URL identified is https://vilenefex.ru/wix?keyword=apk+super+mario+bros+2, which likely serves as a gateway to a malicious payload. The ML classifier strongly indicates maliciousness, and the PDF structure suggests an attempt to exploit users through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://vilenefex.ru/wix?keyword=apk+super+mario+bros+2 PDF link annotation
    • https://giwizakewat.weebly.com/uploads/1/3/1/8/131857916/zopewijojigemuj-guwuvomova-tudubeviterega-kixuziku.pdfIn PDF document text
    • https://gojupisot.weebly.com/uploads/1/3/4/0/134016698/fukovasirev.pdfIn PDF document text
    • https://bidefajiwi.weebly.com/uploads/1/3/4/0/134096082/6424682.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448718/normal_60209eac2ea1c.pdfIn PDF document text
    • https://namazowofurap.weebly.com/uploads/1/3/4/3/134372349/10936b16434.pdfIn PDF document text
    • https://bulasenojagaroj.weebly.com/uploads/1/3/4/3/134357248/sunufobisasikipexu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418000/normal_603cb6f315689.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://27420876-d215-4860-9a72-f48db0d0c320.filesusr.com/ugd/4062c2_2d03190c88164831bcf85350462d9317.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dogazisuze/company_profile_design_ppt_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8149d244-69a6-4c30-bec5-03c0faa8e03a/sony_mdr-zx770bn_manual.pdfIn PDF document text
    • https://d52369c8-37f2-40d9-9d5f-d682b3b4a2e4.filesusr.com/ugd/6d5a7b_d624f84867ed4cefa49a6f30caf0a012.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/rutufokedizon/havoc_demon_hunter_guide_icy_veins.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b4bf3435-248e-4358-b36e-dfe2d7688832/how_do_i_program_my_harmony_665_remote.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/62658a64-7773-4aac-a766-854228587990/25355828994.pdfIn PDF document text
    • https://e0a971b2-7104-4718-9e5f-4f17d768618f.filesusr.com/ugd/6d43b6_ad9efd78a45d42acb09c299dc5c8499a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mokixetat/latigigaxozevefuwu.pdfIn PDF document text
    • https://6c892e0d-5736-4b4a-96a3-cd490fd1fe3d.filesusr.com/ugd/1407cd_f2516745f2ca400585462d856898b91b.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tubukeganuji/commentators_guide_tagalog.pdfIn PDF document text
    • https://s3.amazonaws.com/xotomisen/adobe_photoshop_for_android_phone.pdfIn PDF document text
    • https://s3.amazonaws.com/gosete/florida_corporation_annual_report_sample.pdfIn PDF document text
    • https://s3.amazonaws.com/naxozelozude/3d_photo_editor_for_windows_7.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_off0000e61c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE61C 5260 bytes
SHA-256: 471e0171802624caae5040872c63161efd4865c8b14b5bc7067e0823255a4e68
font_01_sfnt_off0000f7e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7E3 15864 bytes
SHA-256: ea5986152799ff55d7d1733aacc32f3518fc8160168b32bd2184e20475420c3c