Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb7a6ffbd5ea681f…

MALICIOUS

PDF

37.6 KB Created: 2020-09-09 19:07:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d0d785786e4691dd19bf92ff448a2e00 SHA-1: 0c70b08b15cd1cad148ff3086d8f343fa679df80 SHA-256: cb7a6ffbd5ea681f74ee2693d1b1b5e7203ac6cc8fd3df101bdf1caa18ad226c
152 Risk Score

Malware Insights

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

The PDF contains a malicious redirector link that is disguised as a crossword puzzle answer, aiming to trick users into clicking it. The ML classifier strongly indicated maliciousness, and the PDF was found to contain a large number of external links, suggesting a link farm or redirection strategy. The primary IOC is the redirector URL, which leads to further malicious infrastructure.

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.link/pify?keyword=guardian+quick+crossword+15067+answers
    • http://files.thelinksconnection.com/uploads/1/3/1/8/131872273/pozus.pdf
    • http://files.fireflies-and-blossoms.com/uploads/1/3/1/6/131637150/1202714.pdf
    • http://files.missmackeysclassroom.com/uploads/1/3/1/1/131163960/0aff56.pdf
    • http://files.journeythroughlifeministries.net/uploads/1/3/1/4/131406893/fojawijoz_lakezetikiru.pdf
    • http://files.thebeveragebutler.com/uploads/1/3/1/4/131438059/63211.pdf
    • http://files.healthycommunitiescoalition.com/uploads/1/3/2/6/132681851/719654.pdf
    • http://files.laurylgaumer.com/uploads/1/3/0/7/130739081/117722.pdf
    • http://zomibapug.fayettelawyer.com/uploads/1/3/2/6/132696280/bb6dc219.pdf
    • https://cdn.shopify.com/s/files/1/0433/9371/2286/files/nubobotib.pdf
    • https://cdn.shopify.com/s/files/1/0431/8648/7455/files/form_7_star_wars.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/46150969179.pdf
    • https://cdn.shopify.com/s/files/1/0431/1000/6940/files/lufeladow.pdf
    • https://cdn.shopify.com/s/files/1/0428/4363/5879/files/88411030285.pdf
    • https://static.usrfiles.com/ugd/55f640_148d2977c6b94b71853c6f21439457ef.pdf
    • https://static.usrfiles.com/ugd/6240f8_7ff35e2598e74845be4ed75f812fd5de.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_off0000534f.bin
455b4f8486c5c3c6effd0e0b045f0761488953d751e2aecb6c0c4481447a3773
pdf-font-stream PDF embedded font (sfnt) at offset 0x534F 5764 bytes
font_01_sfnt_off00006727.bin
2890144a45f4f1ea11a66971a478faa5b71fc6fab935033080e43036e1f785b8
pdf-font-stream PDF embedded font (sfnt) at offset 0x6727 10120 bytes