Malicious PDF — malware analysis report

Static analysis result for SHA-256 57634d1a4ff9f220…

MALICIOUS

PDF

39.6 KB Created: 2020-08-22 15:57:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d7a489d14e78971962e84fac150bb8a5 SHA-1: 3a38cce76edd9484cfe4a4cf9e9ac20a20ddc6e8 SHA-256: 57634d1a4ff9f22079e5fa64e34f7a6a5ac8829bf3a1baf2b1218051df4909ef
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Phishing: Spearphishing Attachment T1059.001 Command and Scripting Interpreter: PowerShell

The PDF contains a link that redirects to malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body and embedded links suggest a lure related to school uniforms, likely a phishing attempt. The ML classifier also strongly flagged this PDF as malicious. The primary IOC is the redirector URL.

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=brampton+manor+primary+school+uniform
    • http://files.armonklions.org/uploads/1/3/1/3/131383251/a396dbacf0ca.pdf
    • http://files.stkittswatersafaris.com/uploads/1/3/1/0/131070109/7544638.pdf
    • https://cdn.shopify.com/s/files/1/0431/9353/2573/files/84822236828.pdf
    • https://cdn.shopify.com/s/files/1/0431/6377/9240/files/93761869430.pdf
    • https://cdn.shopify.com/s/files/1/0432/8423/4396/files/les_alphas__imprimer.pdf
    • https://cdn.shopify.com/s/files/1/0433/4950/8246/files/88946681892.pdf
    • https://cdn.shopify.com/s/files/1/0431/1141/5965/files/89299863483.pdf
    • https://cdn.shopify.com/s/files/1/0428/7230/7875/files/41482264299.pdf
    • https://cdn.shopify.com/s/files/1/0432/7292/9435/files/75792954670.pdf
    • https://cdn.shopify.com/s/files/1/0440/5932/8662/files/search_chrome_history_by_date.pdf
    • https://cdn.shopify.com/s/files/1/0435/6934/8763/files/xarevakufawimune.pdf
    • https://cdn.shopify.com/s/files/1/0432/7381/4171/files/zulaxepivedepexotasakisiz.pdf
    • https://cdn.shopify.com/s/files/1/0430/0580/4698/files/sipewebadeki.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_off00005d4b.bin
8207da24035fdba7c68a4c98580f6784eeb3a33177b5d5456db6e300310d4b38
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D4B 5408 bytes
font_01_sfnt_off00006f87.bin
6d184dce827c57d2db06750de9c3f41f03758fa0b15b38f29ea69dfb8685bc92
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F87 10104 bytes