Malicious PDF — malware analysis report

Static analysis result for SHA-256 31c369d9f537ed4c…

MALICIOUS

PDF

37.5 KB Created: 2020-08-24 03:19:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0d289d1f6d44a5039d84fcc4c6f830e7 SHA-1: a4f42f67e3c2bce3b7324b11af5595a1282cc0ed SHA-256: 31c369d9f537ed4cb82eaf634bafcc9e76f2c4ee2ec669f53c6068f362719a09
152 Risk Score

Malware Insights

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

The PDF contains a prominent link that redirects to a malicious URL, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though heavily obfuscated, contains the same URL and other links, suggesting a lure to external content. The ML classifier strongly flagged this PDF as malicious. The primary attack vector appears to be social engineering via a deceptive link.

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.com/pify?keyword=chama+chama+song+video++3gp
    • http://files.nbsccromercampusscience.com/uploads/1/3/1/8/131856769/lowowewu_lurelejuf_zutab.pdf
    • http://sakopo.allanmasseycenter.com/uploads/1/3/1/0/131070792/221118.pdf
    • http://dixol.monsieurwowk.com/uploads/1/3/0/7/130739173/denufi.pdf
    • https://cdn.shopify.com/s/files/1/0434/7471/4790/files/6662653029.pdf
    • https://cdn.shopify.com/s/files/1/0431/6663/0037/files/sukikumizusugetu.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/77439678162.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/92283418618.pdf
    • https://cdn.shopify.com/s/files/1/0429/6491/0243/files/92874649149.pdf
    • https://cdn.shopify.com/s/files/1/0437/2883/0625/files/xulajipipuvodeziw.pdf
    • https://cdn.shopify.com/s/files/1/0432/2947/9076/files/pozetemabipagusubuwum.pdf
    • https://cdn.shopify.com/s/files/1/0429/2807/9004/files/zopitajilolivu.pdf
    • https://cdn.shopify.com/s/files/1/0433/8122/7670/files/83994206507.pdf
    • https://cdn.shopify.com/s/files/1/0431/3920/3229/files/abstract_algebra_hungerford.pdf
    • https://cdn.shopify.com/s/files/1/0434/7055/3238/files/fabenofotux.pdf
    • https://cdn.shopify.com/s/files/1/0431/7616/5536/files/85980692660.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_off00004af5.bin
db3cafc3f12f6602753966817abc0900357234a44beaa5ce086ddbc6fac73f0c
pdf-font-stream PDF embedded font (sfnt) at offset 0x4AF5 5488 bytes
font_01_sfnt_off00005d8b.bin
b359706f8f04035274fb5bd8011987b691ae79334c4238dad5e823231b3bc277
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D8B 13584 bytes