Malicious PDF — malware analysis report

Static analysis result for SHA-256 55a9ac1868e24cff…

MALICIOUS

PDF

45.3 KB Created: 2020-08-29 12:29:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e714ac53c4a384e6fedafe31034a048c SHA-1: 023434088a333081626c38ea1bc113e13919e80d SHA-256: 55a9ac1868e24cff4e698bd79ab40bd7aafe34929efacb1f45d09e7314fff40b
154 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.cc/wix'. Additionally, it exhibits a PDF link farm heuristic, with numerous links to PDFs hosted on cdn.shopify.com, suggesting a tactic to manipulate search engine results or distribute further malicious content. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, and the document body was largely unreadable, but the presence of the malicious redirector and the link farm strongly indicate a malicious intent to redirect users to harmful sites.

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.cc/wix?keyword=cuando+surge+el+positivismo
    • https://cdn.shopify.com/s/files/1/0434/0714/7166/files/beats_audio_apk_no_root.pdf
    • https://cdn.shopify.com/s/files/1/0434/0659/0104/files/voziriwew.pdf
    • https://cdn.shopify.com/s/files/1/0427/9150/1990/files/43642436126.pdf
    • https://cdn.shopify.com/s/files/1/0430/2897/1681/files/wakazav.pdf
    • https://cdn.shopify.com/s/files/1/0431/5699/6245/files/9681183456.pdf
    • https://cdn.shopify.com/s/files/1/0431/4651/0498/files/gutozalixa.pdf
    • https://cdn.shopify.com/s/files/1/0437/5710/9402/files/89855598201.pdf
    • https://cdn.shopify.com/s/files/1/0431/5083/5876/files/2904411820.pdf
    • https://cdn.shopify.com/s/files/1/0433/0127/3750/files/59347397491.pdf
    • https://cdn.shopify.com/s/files/1/0438/4073/3341/files/tutorial_blender_bahasa_indonesia.pdf
    • https://static.usrfiles.com/ugd/c12414_2104e827b635416b84b8a8c4700bd8e3.pdf
    • https://static.usrfiles.com/ugd/b8c837_cf53d8e365f34b8cb2a280aba733265a.pdf
    • https://static.usrfiles.com/ugd/b8c837_3bf3aa1a346e405286e7181b0cad3c62.pdf
    • https://static.usrfiles.com/ugd/b8c837_a7543a49c0ef427ab294ad4b80b9a20b.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_off0000749a.bin
c8dfffbceacce5b8f5acba2723df1dfc0884cba8ad58886501051f920be4b802
pdf-font-stream PDF embedded font (sfnt) at offset 0x749A 5244 bytes
font_01_sfnt_off00008660.bin
e1f2eb1d5d17624c7ebf42745b14fd234a9ae10914fd8b6f911356651a0dfe49
pdf-font-stream PDF embedded font (sfnt) at offset 0x8660 10016 bytes