Malicious PDF — malware analysis report

Static analysis result for SHA-256 857e61c8e032f1e4…

MALICIOUS

PDF

42.0 KB Created: 2020-09-04 23:25:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 848775d612305d8f9dd2fd7774666a01 SHA-1: f09d08b451c89b16a2505590ba98084e90f596ea SHA-256: 857e61c8e032f1e492c975bd66824a00e80138c3a445ef3ccc163db88993b8cb
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with one identified as a malicious redirector. The document body, though heavily obfuscated, includes the same malicious URL and other PDF links, suggesting an attempt to drive traffic to potentially harmful content. The ML classifier strongly indicated maliciousness, supporting the presence of a malicious redirector.

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.club/wix?keyword=game+bloody+roar+4
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/96a426_2e99875e3f3b43a9bdb6566039851bf4.pdf
    • https://static.usrfiles.com/ugd/44b221_d15a0a24d5e341c5b3ab1fa251099bbe.pdf
    • https://static.usrfiles.com/ugd/3d7af5_fe860d8c95b446d1925b4278d5a8349b.pdf
    • https://cdn.shopify.com/s/files/1/0432/6732/6110/files/64068716162.pdf
    • https://cdn.shopify.com/s/files/1/0435/7623/0046/files/wanting_memories_sheet_music.pdf
    • https://static.usrfiles.com/ugd/77eba6_f6210814159c4c26aff6049afb705b90.pdf
    • https://static.usrfiles.com/ugd/8b97dd_99aea75b8ce44b67b1f3d5dc70c5346f.pdf
    • https://static.usrfiles.com/ugd/be19e1_c705dcf406c64d01abf09dc4d7132ccc.pdf
    • https://cdn.shopify.com/s/files/1/0430/7202/8833/files/75490835150.pdf
    • https://cdn.shopify.com/s/files/1/0436/1846/7997/files/porigakuzugaderewuviz.pdf
    • https://cdn.shopify.com/s/files/1/0431/8697/8984/files/negeruk.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/
    • https://savannah.gnu.org/projects/freefont/
    • http://www.gnu.org/licenses/
    • http://www.gnu.org/copyleft/gpl.html
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000055b8.bin
01ac34376b7092400a12f9c5b46029046d686b565a1181b560d79e3eb0283013
pdf-font-stream PDF embedded font (sfnt) at offset 0x55B8 6832 bytes
font_01_sfnt_off00006708.bin
d11ce4ee20907bde73517d93530ceff66082a93ec62ab93717a640a9d066d008
pdf-font-stream PDF embedded font (sfnt) at offset 0x6708 5156 bytes
font_02_sfnt_off00007887.bin
06fc94b380397f344dd5e0cd137e84d2646435368b59f6b9487f287cd2338ca3
pdf-font-stream PDF embedded font (sfnt) at offset 0x7887 10244 bytes