Malicious PDF — malware analysis report

Static analysis result for SHA-256 a275e32c61b7f481…

MALICIOUS

PDF

40.3 KB Created: 2020-08-27 13:33:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ebe82f403ce4cf155f42e92fcb66b46d SHA-1: 8b72e0326cb140d491906dd7412a638e86cdd0fb SHA-256: a275e32c61b7f4813b87bf4b237ee4eaee3ac836c3a6d843acc36e8f1f801cba
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a large number of embedded links, many of which point to Shopify domains hosting other PDFs, and one critical link to a known malicious redirector. The document body, though heavily obfuscated, contains the URL for the malicious redirector, suggesting the document's primary purpose is to drive traffic to this malicious site. The ML classifier also strongly indicated maliciousness.

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.com/pify?keyword=algebra+connections+chapter+7+answers
    • http://files.doyogawithchelsea.com/uploads/1/3/0/9/130969926/ed6e20133c0.pdf
    • http://xagumap.kidsks.org/uploads/1/3/1/6/131606289/d5ef8c48d.pdf
    • http://files.turningpointtutors.org/uploads/1/3/1/8/131856160/wolij.pdf
    • https://cdn.shopify.com/s/files/1/0432/6519/6197/files/whatsapp_gold_mod_apk_free.pdf
    • https://cdn.shopify.com/s/files/1/0440/0116/5462/files/zixituxojosizokan.pdf
    • https://cdn.shopify.com/s/files/1/0429/0481/3721/files/95268560314.pdf
    • https://cdn.shopify.com/s/files/1/0432/0631/2091/files/nawevebu.pdf
    • https://cdn.shopify.com/s/files/1/0438/4115/9333/files/najaf.pdf
    • https://cdn.shopify.com/s/files/1/0428/9318/1095/files/daketisopuzarowudob.pdf
    • https://cdn.shopify.com/s/files/1/0434/2182/7239/files/mulunekemosudexog.pdf
    • https://cdn.shopify.com/s/files/1/0433/7706/6145/files/btec_sport_level_3_book.pdf
    • https://cdn.shopify.com/s/files/1/0427/7311/9143/files/array_sort_java.pdf
    • https://cdn.shopify.com/s/files/1/0431/7511/6964/files/33474893038.pdf
    • https://cdn.shopify.com/s/files/1/0431/7688/6431/files/93295098076.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_off00005ece.bin
8ae758c41e11edc22b1299984ddaf26ddd0e8ead2b6f08389096c43d2d0f8ca8
pdf-font-stream PDF embedded font (sfnt) at offset 0x5ECE 5496 bytes
font_01_sfnt_off00007188.bin
24fca6a45734f4a62afacd66a4d6a1a208a64f6c6abcf7d6ab3b417ca0b11b87
pdf-font-stream PDF embedded font (sfnt) at offset 0x7188 10152 bytes