Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f16eca054da6b06…

MALICIOUS

PDF

55.1 KB Created: 2020-08-09 06:18:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 27a119ea845167d28b4c502b7a6a5fb4 SHA-1: f1ed33bde85431ce576c9b3074a1ecc8ca2befad SHA-256: 3f16eca054da6b06f37a7b31e1c28fcf37ed9b3ab28dfcb3c265142605b96a41
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of embedded links, with one specifically pointing to a known malicious redirector. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' and 'PDF_SEO_LINK_FARM' indicate that the document is designed to lure users to malicious sites. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted, but the primary attack vector appears to be the malicious links within the document.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://ttraff.ru/pify?keyword=android+java+development+tutorial+pdf
    • http://files.artsphynx.com/uploads/1/3/0/9/130969306/4782945.pdf
    • http://files.grccny.org/uploads/1/3/1/8/131871424/2405232.pdf
    • http://files.homeschoolclick.com/uploads/1/3/2/6/132681264/waniriwejafeg.pdf
    • http://files.abulaishbarbara.com/uploads/1/3/0/7/130738806/sizegalowokol.pdf
    • https://cdn.shopify.com/s/files/1/0433/4475/6901/files/36697550704.pdf
    • https://cdn.shopify.com/s/files/1/0446/3457/0915/files/android_based_attendance_system.pdf
    • https://cdn.shopify.com/s/files/1/0439/2599/5688/files/anime_minecraft_skins.pdf
    • https://cdn.shopify.com/s/files/1/0433/1490/5256/files/62360201298.pdf
    • https://cdn.shopify.com/s/files/1/0437/2060/5848/files/anormalidades_de_los_eritrocitos.pdf
    • https://cdn.shopify.com/s/files/1/0429/7523/2153/files/83235332938.pdf
    • https://cdn.shopify.com/s/files/1/0437/7785/1550/files/reese_16k_5th_wheel_hitch.pdf
    • https://cdn.shopify.com/s/files/1/0430/2703/8369/files/convert_foxit_to_word.pdf
    • https://cdn.shopify.com/s/files/1/0446/2634/6147/files/google_form_webhook.pdf
    • https://cdn.shopify.com/s/files/1/0437/5432/4117/files/bujaju.pdf
    • https://cdn.shopify.com/s/files/1/0438/4981/0070/files/26994450050.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000098d1.bin
eba748de8a3f1c9ae48d0ad762d774bc137de0ff6a7af7bc9e87bacd2b7e812f
pdf-font-stream PDF embedded font (sfnt) at offset 0x98D1 5132 bytes
font_01_sfnt_off0000aa42.bin
5adab72cf1256d976ff2afb4a8222d0c891c4e291f6845eb63e61dd641f6e2be
pdf-font-stream PDF embedded font (sfnt) at offset 0xAA42 11004 bytes