Malicious PDF — malware analysis report

Static analysis result for SHA-256 7ed8ea8e5fdb2358…

MALICIOUS

PDF

42.0 KB Created: 2020-08-14 22:57:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e66aff51ddbf11059a783bff17b674d5 SHA-1: 64588e6a517d361190cbcb90573278f228b633f4 SHA-256: 7ed8ea8e5fdb23586882dbe8bd3275ea2cec8d760979ad9db7e78681d971a66f
154 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, many of which point to Shopify domains, but one critical link directs to a known malicious redirector. The document body, though partially corrupted, suggests a lure related to educational worksheets. The ML classifier strongly flagged this PDF as malicious, indicating a high probability of malicious intent. The primary attack vector appears to be social engineering through deceptive links within the document.

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/wb?keyword=worksheet%20based%20on%20average%20for%20class%205
    • http://fazolu.tongaheadstones.net/uploads/1/3/1/4/131483281/dagug-vulolinukavad.pdf
    • https://cdn.shopify.com/s/files/1/0438/2749/5074/files/rutudovitunure.pdf
    • https://cdn.shopify.com/s/files/1/0427/8150/7740/files/logorasojopewafalize.pdf
    • https://cdn.shopify.com/s/files/1/0437/0441/8459/files/babovobevemuwatijori.pdf
    • https://cdn.shopify.com/s/files/1/0433/1244/7652/files/kujafesubegadi.pdf
    • https://cdn.shopify.com/s/files/1/0438/4541/9165/files/99_crafting_guide.pdf
    • https://cdn.shopify.com/s/files/1/0432/7030/7995/files/sobom.pdf
    • https://cdn.shopify.com/s/files/1/0428/2908/6876/files/16799609582.pdf
    • https://cdn.shopify.com/s/files/1/0435/2317/8656/files/50800972922.pdf
    • https://cdn.shopify.com/s/files/1/0435/0581/1608/files/81807825763.pdf
    • https://cdn.shopify.com/s/files/1/0434/3041/2454/files/deficiencia_de_vitamina_b8.pdf
    • https://cdn.shopify.com/s/files/1/0427/8901/1612/files/61987620109.pdf
    • https://cdn.shopify.com/s/files/1/0436/5172/7513/files/online_reservation_form.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_off0000649e.bin
e290d30db9b27e27854d593c16b3cdeaff1ee08ed5ba06de04e47128f4cf682d
pdf-font-stream PDF embedded font (sfnt) at offset 0x649E 5684 bytes
font_01_sfnt_off00007808.bin
d1a6b20292e9dece06ee8c8130876ef87384c6ee9f1460ca484d531c9549c9e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x7808 10220 bytes