Malicious PDF — malware analysis report

Static analysis result for SHA-256 26a71dda5ab5ccfc…

MALICIOUS

PDF

45.4 KB Created: 2020-10-31 04:03:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 99aca9d5a24f4707f0dd98e298a4a450 SHA-1: 775cf7c1512e72195489f27e1c0947ed936a012a SHA-256: 26a71dda5ab5ccfc979737609f4e8b4e00027dc0aeafa6f83365d8417c7d0384
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to redirector infrastructure or potentially malicious content. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK specifically flags the URL https://cctraff.ru/aws?keyword=writing+an+informative+essay+about+making+sacrifices+prewriting as malicious. The ML classifier also strongly indicated maliciousness. The document body itself appears to be obfuscated or corrupted, but the presence of numerous links suggests a link farm or redirection attack.

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://cctraff.ru/aws?keyword=writing+an+informative+essay+about+making+sacrifices+prewriting
    • https://cdn-cms.f-static.net/uploads/4377931/normal_5f9c9c56b6a1a.pdf
    • https://gejovekozeja.weebly.com/uploads/1/3/4/4/134401956/tokazejuba.pdf
    • https://dutitujazekap.weebly.com/uploads/1/3/0/8/130814390/7971455.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0438/8831/2488/files/marvels_iron_man_3_-_jarvis_apk.pdf
    • https://cdn.shopify.com/s/files/1/0479/3237/5207/files/wuzimatotip.pdf
    • https://cdn.shopify.com/s/files/1/0501/5430/7774/files/koxigasukizime.pdf
    • https://cdn.shopify.com/s/files/1/0432/1922/2687/files/insinkerator_model_sst-fltr_manual.pdf
    • https://cdn.shopify.com/s/files/1/0496/2700/5094/files/sefodivipogazune.pdf
    • https://cdn.shopify.com/s/files/1/0428/4160/4263/files/transmission_of_heat_class_11.pdf
    • https://cdn.shopify.com/s/files/1/0504/3011/6014/files/54425528682.pdf
    • https://cdn.shopify.com/s/files/1/0438/2425/1042/files/gestion_de_riesgos_pmbok.pdf
    • https://s3.amazonaws.com/numegubowalonan/60254706890.pdf
    • https://cdn.shopify.com/s/files/1/0436/8377/4614/files/90146708918.pdf
    • https://s3.amazonaws.com/rizijubovapuk/wovikoruforufe.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007185.bin
6f2ce44fd6bd81c1bdb4c6b79e73b04e26cb2d5c354cdafd1454752bd992abb4
pdf-font-stream PDF embedded font (sfnt) at offset 0x7185 5772 bytes
font_01_sfnt_off0000854a.bin
97c4f7aa2aed68c8835acc075a7915615ff0d5137f87de2802ccdbdb558e459e
pdf-font-stream PDF embedded font (sfnt) at offset 0x854A 10276 bytes