Malicious PDF — malware analysis report

Static analysis result for SHA-256 828f4492ad9b3b9d…

MALICIOUS

PDF

41.9 KB Created: 2020-08-16 22:14:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 4504e8a0c1a34336fff9c843f03bd352 SHA-1: 425a0d1fe59903b56a2ad7def3dfa4fff113e41a SHA-256: 828f4492ad9b3b9d07728d14388ff35827d5acc662ed820fb27b7f8d1f410beb
154 Risk Score

Malware Insights

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

The PDF contains embedded links that point to a known malicious redirector, indicating an attempt to lure the user to a harmful site. The heuristic PDF_SEO_LINK_FARM also suggests a large number of outbound links, many of which are to PDF files, potentially for SEO manipulation or further distribution. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, but the embedded URLs are the primary indicators of malicious intent.

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=converting+units+of+mass+worksheet
    • http://files.abridgedinvesting.com/uploads/1/3/0/7/130740138/6296899.pdf
    • http://files.beyondtolerancewichita.org/uploads/1/3/0/8/130813769/7068502.pdf
    • http://files.acds-clsa.com/uploads/1/3/1/3/131379443/sotoges.pdf
    • http://files.thediplip.com/uploads/1/3/0/9/130969874/4647438.pdf
    • http://files.beckywidschwenter.com/uploads/1/3/0/7/130739063/lebulefidojom_duzozufigef.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/2229/3920/files/56928619782.pdf
    • https://cdn.shopify.com/s/files/1/0429/0537/0791/files/18561829655.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/xiwisabimetabif.pdf
    • https://cdn.shopify.com/s/files/1/0431/1013/8017/files/gubobowov.pdf
    • https://cdn.shopify.com/s/files/1/0430/4211/1637/files/41978302930.pdf
    • https://cdn.shopify.com/s/files/1/0432/1994/3579/files/tasasexiduguriduvulisan.pdf
    • https://cdn.shopify.com/s/files/1/0435/0522/1784/files/synapse_rc7_custom_ui.pdf
    • https://cdn.shopify.com/s/files/1/0427/6954/7431/files/kufume.pdf
    • https://cdn.shopify.com/s/files/1/0435/4765/6351/files/dutupuronesurel.pdf
    • https://cdn.shopify.com/s/files/1/0430/4073/5381/files/39099052331.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000655e.bin
3c785f70c2a5934b1efae09946d4c5c62f80369cd98325d103f81ba6c300889a
pdf-font-stream PDF embedded font (sfnt) at offset 0x655E 5268 bytes
font_01_sfnt_off0000773b.bin
8418a0dcd284781f3a636791f5b79edfae67845fea9dac9e5a86a4ad7c84dcdb
pdf-font-stream PDF embedded font (sfnt) at offset 0x773B 10348 bytes