Malicious PDF — malware analysis report

Static analysis result for SHA-256 4687a56eba8b4d52…

MALICIOUS

PDF

38.6 KB Created: 2020-08-09 19:40:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2c699cf40072073e5fd1caf9b3639f79 SHA-1: f9f3ed175aea18d4212c1d058c0230fbba497187 SHA-256: 4687a56eba8b4d5293f63c32481f16f8dd447e5259dc9d22c45be9e7c2cc5b15
154 Risk Score

Malware Insights

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

The PDF contains a mass of external links, with one specifically pointing to a known malicious redirector. The document body, though corrupted, contains text related to academic papers and the string 'skripsi kualitatif akuntansi perpajakan pdf', suggesting a lure to disguise the malicious intent. The ML classifier also strongly indicated maliciousness. The primary IOC is the redirector URL which likely leads to further malicious content.

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/pify?keyword=skripsi+kualitatif+akuntansi+perpajakan+pdf
    • http://files.alexjtaylor.com/uploads/1/3/1/4/131437982/0488b6c443e519.pdf
    • http://nuzutes.latoyanelson.com/uploads/1/3/1/3/131380600/9418627.pdf
    • http://files.sicilyreview.com/uploads/1/3/1/4/131406344/nadajemuk.pdf
    • https://cdn.shopify.com/s/files/1/0428/9848/9503/files/5th_edition_monster_manual_download.pdf
    • https://cdn.shopify.com/s/files/1/0435/3284/5207/files/vefuxorutise.pdf
    • https://cdn.shopify.com/s/files/1/0430/8677/4436/files/sutuzorigomuwop.pdf
    • https://cdn.shopify.com/s/files/1/0432/6942/3269/files/dewukumupinuwoxetilufuwa.pdf
    • https://cdn.shopify.com/s/files/1/0437/9148/3042/files/gary_moore_parisienne_walkways.pdf
    • https://cdn.shopify.com/s/files/1/0437/8856/6680/files/damudibujosemofu.pdf
    • https://cdn.shopify.com/s/files/1/0434/5203/9328/files/tiviboxakabiz.pdf
    • https://cdn.shopify.com/s/files/1/0432/8026/9462/files/weranonavakipujulofit.pdf
    • https://cdn.shopify.com/s/files/1/0440/6090/1528/files/76116686761.pdf
    • https://cdn.shopify.com/s/files/1/0432/8099/0366/files/lexizorirari.pdf
    • https://cdn.shopify.com/s/files/1/0432/7889/3214/files/ear_acupuncture_points_chart.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_off00005a74.bin
1b1bcc0eb77350e6a2207767155c6eedd43fd92420b33bfde97358c42ba6758f
pdf-font-stream PDF embedded font (sfnt) at offset 0x5A74 5276 bytes
font_01_sfnt_off00006c7e.bin
cd0e23e911669cdefbd5fc0d5b014f8fc62b05d5e7b88a15249424957efcbd30
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C7E 9736 bytes