Malicious PDF — malware analysis report

Static analysis result for SHA-256 f163b354d4060310…

MALICIOUS

PDF

81.8 KB Created: 2021-10-07 12:33:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8612ef76ba60a2ccccf4c4512f82754d SHA-1: ee3b6b6c2b8b8d76d6e281d054171fb1cb5b4d45 SHA-256: f163b354d406031076051a13eded3b0e872bb06a05addb6eac75a4c13ddfeb9c
156 Risk Score

Malware Insights

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

The file was identified as malicious by ClamAV and an ML classifier. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to potentially compromised or disposable hosting sites. These links are likely intended to lure users to phishing pages or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/nomilinediziluge.pdf In PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161425f7dea5ce---loxikosigotogozunez.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1615e996446c80---76975047816.pdfIn PDF document text
    • https://aildf.in/userfiles/file/ranuzexamabarafibif.pdfIn PDF document text
    • http://hyunshin.net/userfiles/file/88581904098.pdfIn PDF document text
    • https://cvssteelex.com/ckfinder/userfiles/files/91367338955.pdfIn PDF document text
    • http://studiorumeo.it/userfiles/files/vemuto.pdfIn PDF document text
    • http://nissanotogovap.com/uploads/images/files/xabumanufolaxenamajodas.pdfIn PDF document text
    • https://malabarmail.com/ckfinder/userfiles/files/90096829649.pdfIn PDF document text
    • https://bdata.vn/upload/files/65585014890.pdfIn PDF document text
    • http://viral-list-monster.com/ckfinder/userfiles/publics/files/ponorulelonuparaxa.pdfIn PDF document text
    • https://primer-spb.ru/files/files/wakirotefaseso.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/16147759279737---rilopomipiloduronefum.pdfIn PDF document text
    • https://gastrotest.co/ckfinder/userfiles/files/89153295231.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/godibewiwazesaw.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140da4484801---nejonunagevifa.pdfIn PDF document text
    • http://sallytour.com/FileData/ckfinder/files/20210929_8C974B31E5630D4C.pdfIn PDF document text
    • http://photou.cc/ckfinder/userfiles/files/dudamukurozugizolodo.pdfIn PDF document text
    • http://duythuc-bearing.vn/uploads/userfiles/file/xijalowubijowixoxanerif.pdfIn PDF document text
    • https://lean-ds.com/upload/editor/file/wavokezavuwope.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/55780588801.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd5b128097---29339394799.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615d12c13efb6---porisekupakutawazib.pdfIn PDF document text
    • http://ctkupavna.ru/upload/file/defipilopog.pdfIn PDF document text
    • http://keacg.com/upload/files/xowed.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=long+in+a+toothPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB2E 9900 bytes
SHA-256: 6ae0d24b5056086f75920013e521e3c702681819fdee1f63e0f8b6c73225e14d
font_01_sfnt_off0000f0ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0EC 19068 bytes
SHA-256: 0dadffe75d1d7c66ec8d7d5e371f45866c0b1cfae97b73c78011a2debb468e8f
font_02_sfnt_off000121f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1