Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7c9fe00e23a756f…

MALICIOUS

PDF

143.5 KB Created: 2020-12-25 02:24:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 428d6fdc010f03c4d60f70d1fd45222f SHA-1: 8525925eeeab798ea018db58b2ba190170a34506 SHA-256: b7c9fe00e23a756f18f6eeb0fcc6d40d989244e490ef0d59c1e2932d237742bc
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous external links to other PDF documents hosted on disposable domains, indicating a link farm or SEO manipulation scheme. The ClamAV detection and ML classifier also flagged this file as malicious. The embedded URLs suggest a phishing or malware distribution attempt, likely using the PDF as a lure to drive traffic to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6747

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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 https://trafficel.ru/aws?utm_term=tamil+alphabet+letters+pdf PDF link annotation
    • https://walijogopabo.weebly.com/uploads/1/3/0/7/130776167/5300225.pdfIn PDF document text
    • https://sexabadipeg.weebly.com/uploads/1/3/4/6/134684930/59c73f1.pdfIn PDF document text
    • https://topemarepebide.weebly.com/uploads/1/3/4/3/134316461/b303a4.pdfIn PDF document text
    • https://kigilejujagenit.weebly.com/uploads/1/3/1/4/131438309/681e6.pdfIn PDF document text
    • https://biwomewiwuxe.weebly.com/uploads/1/3/4/1/134131409/tuzubuted.pdfIn PDF document text
    • https://resumasilazivo.weebly.com/uploads/1/3/4/5/134509929/jikuzufanopipo.pdfIn PDF document text
    • https://jawuvufos.weebly.com/uploads/1/3/4/8/134856807/mobawilolezosufo.pdfIn PDF document text
    • http://fedorahosted.org/lohitIn 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://s3.amazonaws.com/leguvefu/92679071025.pdfIn PDF document text
    • https://s3.amazonaws.com/wonoti/asme_b31._10.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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 8

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off0001686e.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1686E 48836 bytes
SHA-256: f82234cf8fe7777249c60fe5ba9d3e8b5ef52a3b6a3c2801a9d3ee1b7bf54562
font_00_sfnt_off000147c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147C7 6444 bytes
SHA-256: b2eb716f9f1f9b32722e1ea04f9b39d21e8999039eb4c7f2f5ede24790997a64
font_01_sfnt_off000157b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x157B7 4944 bytes
SHA-256: 8ebf58b1bcb4f6d1afa0b0c6a6884d075bfb08ecc12daa7a8f66c0d393976ab1
font_03_sfnt_off0001bd93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BD93 17480 bytes
SHA-256: e46e395f3a1ece32837c6115e4fce27a555a37a58b3d5cf426969f249a01ee47
font_04_sfnt_off0001f1a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1F1A2 16360 bytes
SHA-256: a177c695115712b0de48f9fdad31280576b6f3a51c8fb190aa9712f165116d91
font_05_sfnt_off00020790.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x20790 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378
font_06_sfnt_off00021590.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x21590 2480 bytes
SHA-256: 2694bcef0afaa4b739418ef25af8c3b4e55e2d06b59fce0e827502d6bffdf3e6
font_07_sfnt_off00021f9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x21F9D 6084 bytes
SHA-256: 0bbd385887db5074fbd87256d70f98a882c9353f1362fd6c1377f0ce146e0394