Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1daab7ac2e94da8…

MALICIOUS

PDF

39.5 KB Created: 2020-08-14 01:58:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1bfa1648d6bb680995f6321448827fd1 SHA-1: 4f17b66d41f3a2060d46862cba5091710062fbc3 SHA-256: a1daab7ac2e94da8749e1053d990a3b9d0172245db244902ac89c2258f0f18b6
152 Risk Score

Malware Insights

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

The PDF contains a link to a redirector URL, which is a common tactic for delivering malware or phishing pages. The document body, though heavily obfuscated, contains the same redirector URL and several other URLs pointing to PDF files, suggesting a link farm or a lure to download further content. The ML classifier also strongly indicated maliciousness.

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=asyndeton%20and%20polysyndeton%20worksheet
    • http://merujaf.jocelynphotoblogs.co.uk/uploads/1/3/1/4/131453870/415008e7.pdf
    • http://files.kraskoyarabians.com/uploads/1/3/2/6/132682640/0105e1a0e451653.pdf
    • http://files.framedbytheword.com/uploads/1/3/2/7/132710630/kabetafakaxoga-kuzavani-xikugepu-miniralizapi.pdf
    • https://cdn.shopify.com/s/files/1/0435/3091/1899/files/jim_stoppani_workouts.pdf
    • https://cdn.shopify.com/s/files/1/0433/5324/3806/files/29651299261.pdf
    • https://cdn.shopify.com/s/files/1/0436/0624/5539/files/architectural_drawing_checklist.pdf
    • https://cdn.shopify.com/s/files/1/0435/5633/9861/files/mibodifawesekutuxobapazeg.pdf
    • https://cdn.shopify.com/s/files/1/0431/3304/2839/files/herluf_bidstrup_book.pdf
    • https://cdn.shopify.com/s/files/1/0435/5453/7624/files/fibonacci_sequence_javascript.pdf
    • https://cdn.shopify.com/s/files/1/0431/9143/5422/files/10391748869.pdf
    • https://cdn.shopify.com/s/files/1/0436/0388/6238/files/miperi.pdf
    • https://cdn.shopify.com/s/files/1/0432/3010/1668/files/sql_format_amount_with_commas.pdf
    • https://cdn.shopify.com/s/files/1/0434/2641/4749/files/never_be_alone_shawn_mendes_piano_sheet_music.pdf
    • https://cdn.shopify.com/s/files/1/0436/2466/1154/files/bootstrap_phylogeny.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_off00005c5b.bin
8fc644e7c0a3f72708dab5cc5f08eb1098cdac70c5029475a3dd5de832807f1c
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C5B 5296 bytes
font_01_sfnt_off00006e69.bin
97aa7f58895c6bdd547f2b3bff7282f1db986a974d1f980207c0268f1b726889
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E69 10268 bytes