Malicious PDF — malware analysis report

Static analysis result for SHA-256 5682d7aa35e771a2…

MALICIOUS

PDF

84.4 KB Created: 2021-09-23 11:09:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c8dad1eb549602d39befde8e515ddfa5 SHA-1: d04b41401c1d23483c1d04db8ef02944b2196af7 SHA-256: 5682d7aa35e771a25a41cfd42948c365f9d65ea2a80e5b39a84e9fd12ae7b40a
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many embedded URLs pointing to potentially compromised or disposable domains. The primary attack pattern involves luring users to external sites, which could lead to phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://detector-billetes.com/Imagenes/file/gadanewovelukavudomoxixez.pdf
    • http://kastely-vacduka.hu/fileok/file/80277001562.pdf
    • https://1877painters.com/FCKeditor/file/dosetopotapenexukurejew.pdf
    • http://vdadanang.vn/app/webroot/assets/files/31247439231.pdf
    • https://luathoanghuy.com/uploads/files/26782052988.pdf
    • https://linardi.ru/files/file/69082289360.pdf
    • https://kirbas.com/img/uploaded/file/66321184995.pdf
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16131fc5ab103c---gabeketekafijowipitupu.pdf
    • https://briljant-maleri.se/UserFiles/files/sasuzideka.pdf
    • http://adance0112.com/upfile/editor/file/kumapumirevofevosux.pdf
    • https://globalybm.com/ckfinder/userfiles/files/1631833298.pdf
    • http://bhavalaya.org/ckfinder/userfiles/files/69079712049.pdf
    • http://www.awakohchang.com/image/upload/File/orafepixajedoz.pdf
    • https://girisimhaber.com/uploads/file/88818891562.pdf
    • http://netichikawaya.com/userfiles/file/xekulevakudu.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16132282fecae1---38637341125.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/93924594b5d5c8492d8f8b67f866f846/wukovig.pdf
    • http://boras-sjuharad.boj.se/uploads/userfiles/files/jelolusakuvojurizexikafo.pdf
    • https://nocnepal.org.np/ckfinder/userfiles/files/biwanowuxokunaxibirapower.pdf
    • http://pelejas.com/IMAGENS/CKFINDER/files/wuwozamanib.pdf
    • http://k-yoga.org/file_upload/spaw_upload/file/20210923130215.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613df68d6a1ee---38769641339.pdf
    • https://bank-kredit.at/ckfinder/userfiles/files/31781687357.pdf
    • http://www.serenissimaservizi.com/files/92911466672.pdf
    • http://morpheus-architects.com/file_media/file_image/file/98883243664.pdf
    • https://willes-gb.com/uploads/files/202109131322341314.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=nova+launcher+font+change
    • 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/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e31f.bin
da1d786871097777f7e835ca290772323430c6052bfefb9f9f0e5c241478df81
pdf-font-stream PDF embedded font (sfnt) at offset 0xE31F 10500 bytes
font_01_sfnt_off0000fb0e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB0E 16792 bytes
font_02_sfnt_off00011320.bin
fb3121b35b947d5b8a10e42e083db150004643b1b5be7d702164a3d0d0b54d89
pdf-font-stream PDF embedded font (sfnt) at offset 0x11320 18644 bytes