Malicious PDF — malware analysis report

Static analysis result for SHA-256 25b491ce956ca6e5…

MALICIOUS

PDF

38.3 KB Created: 2020-08-29 04:04:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dacb6b0520c6459d109902a231d5afc3 SHA-1: d3282975fc68e4e20bc439e95eea786f31c4f042 SHA-256: 25b491ce956ca6e5c15b4a63bf0f99de1c46f61630a299c8544e0f09667238d3
152 Risk Score

Malware Insights

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

The PDF file was flagged by multiple critical heuristics for containing malicious redirector links and a large link farm. The ML classifier also strongly indicated maliciousness. The document body contains obfuscated text and embedded URLs, including a primary redirector URL. The presence of numerous links suggests an attempt to lure users to malicious sites, potentially for phishing or malware distribution.

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.ru/wix?keyword=nokia+g-240w-a+login
    • https://static.usrfiles.com/ugd/b8c837_da597b5dc8d14027ba045ec08f63c16b.pdf
    • https://static.usrfiles.com/ugd/b8c837_c07078fac9d04a0caddf1b60a8167997.pdf
    • https://static.usrfiles.com/ugd/b8c837_fa7b1e0f07fe4643adc12cdd748febc5.pdf
    • https://cdn.shopify.com/s/files/1/0437/9744/6818/files/86620056508.pdf
    • https://static.usrfiles.com/ugd/b8c837_0f3b9c2cb1cd470db88665cd18bc7821.pdf
    • https://static.usrfiles.com/ugd/b8c837_bdf2f87b1ad24e158f538882c5727b89.pdf
    • https://static.usrfiles.com/ugd/b8c837_bbbf0d3f14394fbb96d46ad2b79530c3.pdf
    • https://static.usrfiles.com/ugd/b8c837_2b3463456e4549edbdb81a62087af4a4.pdf
    • https://cdn.shopify.com/s/files/1/0430/4509/3533/files/22187369015.pdf
    • https://cdn.shopify.com/s/files/1/0438/5452/8677/files/48384656893.pdf
    • https://cdn.shopify.com/s/files/1/0437/6153/3082/files/jenadawejunizivojom.pdf
    • https://cdn.shopify.com/s/files/1/0447/9274/2049/files/57527926303.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_off00005842.bin
f9b5163a816f34abaf5a7572e2d72e2d199fb69c64a785ba14e530c2ca0e2be6
pdf-font-stream PDF embedded font (sfnt) at offset 0x5842 5096 bytes
font_01_sfnt_off000069d0.bin
02a6b0ea3ecb94aa24015840c260061d0755e3eb02965d026695b165e429d162
pdf-font-stream PDF embedded font (sfnt) at offset 0x69D0 10184 bytes