Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b37beb373ddf09d…

MALICIOUS

PDF

72.5 KB Created: 2020-04-05 12:29:57 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: e21fb83a69a3652e2638a01f3d5dc79d SHA-1: e325b29e3090e64131a59dc2b3d3f2873a5e6efa SHA-256: 9b37beb373ddf09d322f8e49b84b6d5e3c82bc6078f9735e8fdedf319a681a4d
96 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to other PDF files hosted on various domains. This behavior is characteristic of SEO link farming or a mechanism to distribute further malicious content. The ML classifier strongly indicated maliciousness, and the PDF_SEO_LINK_FARM heuristic confirms the suspicious linking pattern. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 4

  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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 http://marcgoesgreen.com/uploads/1/3/1/3/131384028/131384028.html#la+formula+para+calcular+el+volumen+de+un+prisma+pentagonal
    • http://morganvarn.com/uploads/1/3/1/4/131453358/bd114778.pdf
    • http://tranquilomusic.net/uploads/1/3/0/7/130775883/2060980.pdf
    • http://mytexascleaning.com/uploads/1/3/0/7/130740173/gazixe.pdf
    • http://unitedhubgroupinc.net/uploads/1/3/0/3/130313741/mujazaloxigi_bedinebaveb_xijibuguxe.pdf
    • http://mizzoumso.org/uploads/1/3/1/0/131070559/87a0f5429.pdf
    • http://spinonenational.com/uploads/1/3/1/0/131070523/5048659.pdf
    • http://mindsetenrichment.com/uploads/1/3/1/0/131070420/6863739.pdf
    • http://redgoddessboutique.com/uploads/1/3/0/7/130776680/2340795.pdf
    • http://lowcarbnutritionist.com/uploads/1/3/0/5/130551064/6238101.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 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000749d.bin
0233a30d52ae6b58ac6ca5037e3beddfdad2440e24a2cebf3cd7282df968b790
pdf-font-stream PDF embedded font (sfnt) at offset 0x749D 12732 bytes
font_01_sfnt_off000091b1.bin
a2e1bac29bedc2b5a551a0915d65f40893d9b1ac6c01f851eeb68ac99111a9e7
pdf-font-stream PDF embedded font (sfnt) at offset 0x91B1 11704 bytes
font_02_sfnt_off0000b7e0.bin
9e06c65605aefeb5aeb29e124f9924ec5bd430da26318803c768d0e0f459c6d5
pdf-font-stream PDF embedded font (sfnt) at offset 0xB7E0 9084 bytes
font_03_sfnt_off0000d532.bin
83459e82cebe561b9e65dda6a09953c9e35f75e5df0fa62a624e1833cc5b8086
pdf-font-stream PDF embedded font (sfnt) at offset 0xD532 1708 bytes
font_04_sfnt_off0000dd99.bin
aae4d14b29e6957dc2271726d4047f15b2e2a13adb6b3e48c347e6f8248e3469
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD99 18136 bytes
font_05_sfnt_off0000f93b.bin
92bf7f4e5f0606b29e2232d2f95af58aea38299e73160e44490c65bec0f219f6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF93B 8380 bytes