Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c5ef5b8a56c1409…

MALICIOUS

PDF

48.9 KB Created: 2020-08-31 05:18:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: eed462e8bca1a45d977ffeab24c41692 SHA-1: 8e8db475b0c4fb6099bb6d16f0987ac125a020d1 SHA-256: 6c5ef5b8a56c1409b21497d2a2656729e77cc61f485e43f8c8b45aa80987a23c
162 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a link to a known malicious redirector, identified by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though heavily obfuscated, contains a URL that is also flagged as malicious. The presence of a 'download button' lure and the ML classifier's high confidence score further support the malicious nature of this file. No scripts were extracted, but the embedded URL is the primary indicator of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • 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
  • 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/wix?keyword=answers+of+chapter+combustion+and+flame
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://static.usrfiles.com/ugd/3aca14_39e35f3757114cb9aafc68e6f4caa77d.pdf
    • https://static.usrfiles.com/ugd/b8c837_036edfe4fecf43169e19388be727cec1.pdf
    • https://static.usrfiles.com/ugd/136d07_16248d317d0f4fbeb26c536c45e02b86.pdf
    • https://static.usrfiles.com/ugd/b8c837_834f1ea47de1430fbb9741efb9b80c99.pdf
    • https://static.usrfiles.com/ugd/b8c837_0675bf0d342c4dc788b86726e2943cd5.pdf
    • https://cdn.shopify.com/s/files/1/0435/9330/2178/files/sakigovixifuwawanukoli.pdf
    • https://cdn.shopify.com/s/files/1/0428/9167/3763/files/anker_soundcore_flare_user_manual.pdf
    • https://cdn.shopify.com/s/files/1/0432/2040/2337/files/33528607147.pdf
    • https://cdn.shopify.com/s/files/1/0428/0093/9164/files/fomisolabinanagudigeduwok.pdf
    • https://cdn.shopify.com/s/files/1/0439/4529/6027/files/android_mode_nokia_7_plus.pdf
    • https://cdn.shopify.com/s/files/1/0428/9773/5843/files/92757382170.pdf
    • https://cdn.shopify.com/s/files/1/0444/3511/2103/files/appreciative_inquiry_steps.pdf
    • https://cdn.shopify.com/s/files/1/0429/4914/8828/files/23027731960.pdf
    • https://cdn.shopify.com/s/files/1/0429/5933/9674/files/25813704150.pdf
    • https://cdn.shopify.com/s/files/1/0460/7148/0484/files/16146660809.pdf
    • https://cdn.shopify.com/s/files/1/0431/2491/6388/files/30317111076.pdf
    • https://cdn.shopify.com/s/files/1/0433/9276/2006/files/lujugalazudibena.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000072fd.bin
bace8bfa861642b0ee587870937f20503409979153bf57e5597a863f792f8569
pdf-font-stream PDF embedded font (sfnt) at offset 0x72FD 5496 bytes
font_01_sfnt_off00008580.bin
6794354cc9fd3a99ae98502ceb258c0be2ab4e3cd4b03acb048542b122a44d7f
pdf-font-stream PDF embedded font (sfnt) at offset 0x8580 10012 bytes
font_02_sfnt_off0000a7c8.bin
ce7e2e230a41ba6fc2d7d2240890c8289d67876d84a3d076d67c0b48111c8230
pdf-font-stream PDF embedded font (sfnt) at offset 0xA7C8 4324 bytes