Malicious PDF — malware analysis report

Static analysis result for SHA-256 b55681c6b90cc301…

MALICIOUS

PDF

48.6 KB Created: 2020-10-25 17:58:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 2623fe71adb13ca6d8c89eb0b74801f1 SHA-1: 2f91e3899bf833a592164d98bb5bf8640567501e SHA-256: b55681c6b90cc30134f974a4c78939244d33993587b9a7553cc73c7b256dddd4
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to redirector infrastructure, indicating a link farm designed to lead users to malicious sites. The ML classifier also strongly flagged this PDF as malicious. While no scripts were directly extracted, the embedded links are the primary attack vector, likely intended to lure users into downloading further malware or visiting phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://ggtraff.ru/aws?keyword=bureau+of+indian+standards+book+pdf In PDF document text
    • https://cdn-cms.f-static.net/uploads/4373749/normal_5f8a7ac460dc3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365636/normal_5f8735a7c050a.pdfIn PDF document text
    • https://fotejisatowonu.weebly.com/uploads/1/3/2/3/132302873/92dcfdee4b4.pdfIn PDF document text
    • https://tidemipevu.weebly.com/uploads/1/3/0/7/130740592/1848004.pdfIn PDF document text
    • https://buxivadoga.weebly.com/uploads/1/3/0/7/130740323/7911124.pdfIn PDF document text
    • https://jufaxexave.weebly.com/uploads/1/3/0/7/130775513/wikemowewoladoxuso.pdfIn PDF document text
    • https://rikisuluwujufa.weebly.com/uploads/1/3/1/4/131452938/21736d4514.pdfIn PDF document text
    • https://waripeseditalas.weebly.com/uploads/1/3/4/0/134012866/falopeze_serenawetarago_piwegomewir_rosifo.pdfIn PDF document text
    • https://zuwumepegowivos.weebly.com/uploads/1/3/1/0/131069935/zuguvubomawa.pdfIn PDF document text
    • https://xotiroxo.weebly.com/uploads/1/3/0/7/130776105/879138.pdfIn PDF document text
    • https://buliduxefexefux.weebly.com/uploads/1/3/1/6/131636978/4165320.pdfIn PDF document text
    • https://gojemafofapuvog.weebly.com/uploads/1/3/2/6/132681271/a0e20.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366358/normal_5f882d7b85f2c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384304/normal_5f915ab7b55ef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379987/normal_5f8bd71775190.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388158/normal_5f8f583745040.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://cdn.shopify.com/s/files/1/0497/8494/6850/files/nice_guidelines_diabetes_2020.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0498/7486/2247/files/gounod_messe_breve.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/9799/6960/files/pipavebuvaja.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0463/6259/1387/files/difekokemexisotowakipipe.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0501/0056/8221/files/setozekigux.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007121.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7121 5136 bytes
SHA-256: cc0c3d3a312d0c38038cb44200b005391a3abaea6a9152ac199a585e64275545
font_01_sfnt_off000082a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x82A2 10704 bytes
SHA-256: 6602b25812bf2c924d53754dcebfa4ecd602c44ce8a4af39b7fdd802c1835e29
font_02_sfnt_off0000a6ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA6CA 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176