Malicious PDF — malware analysis report

Static analysis result for SHA-256 81e7aaac7af33d01…

MALICIOUS

PDF

52.3 KB Created: 2020-08-24 08:06:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ca7b363e331a6a15543c59f3b3498018 SHA-1: fbdbf6a0970dc92c725a14529163f1b6cbbc5854 SHA-256: 81e7aaac7af33d0125d69cefadb1e299f2be635f4b38c71ca016849592d37eb4
152 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, with one identified as a malicious redirector. The document body, though heavily obfuscated, contains references to 'Cambridge dictionary arabic apk' and the malicious URL, suggesting a lure to a phishing or malware distribution site. The presence of numerous external PDF links, many hosted on Shopify, indicates a link farm designed to improve SEO for malicious content. The ML classifier strongly flagged this PDF as malicious.

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=cambridge+dictionary+arabic+apk
    • http://files.fenianfear.com/uploads/1/3/0/9/130969357/telurus.pdf
    • https://cdn.shopify.com/s/files/1/0428/9301/7247/files/barorreceptores_y_quimiorreceptores.pdf
    • https://cdn.shopify.com/s/files/1/0431/6987/4082/files/povajojoba.pdf
    • https://cdn.shopify.com/s/files/1/0432/2204/0731/files/99665140968.pdf
    • https://cdn.shopify.com/s/files/1/0436/0765/4563/files/handbook_of_practical_cathodic_corrosion_protection.pdf
    • https://cdn.shopify.com/s/files/1/0433/0812/2280/files/32070451740.pdf
    • https://cdn.shopify.com/s/files/1/0435/2186/7930/files/33081547870.pdf
    • https://cdn.shopify.com/s/files/1/0430/8549/6482/files/sasaxekuzopoxakinunoveti.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/12247178291.pdf
    • https://cdn.shopify.com/s/files/1/0431/7750/9020/files/paxideguxodebawerojirage.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off000093c9.bin
53ddb19ea1e3342ad4bbdc43a53d31457bc3fcffb6e9f96655d4fc52fe4ca6e0
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x93C9 27344 bytes
font_00_sfnt_off00005d0c.bin
71eea3c920eefb861461fecf80b59259793e0c2beefd65b35e2d08175a8e68c0
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D0C 5392 bytes
font_01_sfnt_off00006f57.bin
37b642e2ba0457f98631d0685509e8cc1130958f0c9ff74a4acb4b3566ff482d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F57 10620 bytes