Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3a8fda5ab293c55…

MALICIOUS

PDF

93.7 KB Created: 2021-08-17 21:54:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9d551b351b2670eb0efd60ef4c3b5717 SHA-1: cbe7e11db9cf1d86ab30447b44a4e6f2eb8196ba SHA-256: b3a8fda5ab293c557c83e514fce76338e9c4a153bda4aa91ac59b4b6bf76ad72
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of external URIs and link farms strongly supports the classification as a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

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://coretry.ru/uplcv?utm_term=batman+arkham+city+lockdown+apk+data+revdl
    • https://www.avantagesapp.com/uploads/files/72119378956.pdf
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c68f6c3990f---4086964464.pdf
    • https://thietbivesinhanhhuy.com/asset/files/baradigi.pdf
    • http://uniradioweb.info/userfiles/files/kewubapakenebifizomeribu.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ddd65ae28e2---dozevineki.pdf
    • https://coherence.cz/userfiles/file/23258490669.pdf
    • http://yossy.biz/userfiles/file/dofodutupugaxuwijojoxip.pdf
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b999f16ed0b---monasewodaradodebixol.pdf
    • http://peaceinsrilanka.lk/userfiles/file/67607114162.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/pbdm2i2gebn787btf6cucl7hka/fevadudakagalogozodowuxif.pdf
    • http://aelma.com/sites/default/userfiles/file/46139412156.pdf
    • http://klpa.net/userData/board/file/raxodorapedumadiwusafa.pdf
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094410a7fe8a---kubeturexuxajilebolekak.pdf
    • https://topaldanang.vn/uploads/image/files/15501155675.pdf
    • http://galgalesh.com/userfiles/file/zalekazunusolo.pdf
    • http://darstin.com/userfiles/files/vukigubabebokevib.pdf
    • http://newcastlehigh1967-50threunion.com/clients/43248/File/58296186525.pdf
    • http://carzip.biz/files/uploads/files/jafizijevelomat.pdf
    • http://divorce-difficile.fr/userfiles/file/24511025031.pdf
    • https://viceda.com/userfiles/file/munemuvopofasiratugi.pdf
    • http://poultech.net/d/files/fedofazobisolirawi.pdf
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/ed9fa1871fca4655ecb6a33d95b9f6a5/90074731426.pdf
    • http://bukvoznaika.ru/ckfinder/userfiles/files/fanemazetixozimasotelufo.pdf
    • https://expeditions-travel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea5a6ac070---takuzavibedunezukit.pdf
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/a4b5ba913d1cb5a996a9518819eb4c36/kinudivunuxu.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/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000e63b.bin
d3091945cc80f1466ccacb03cae33eabf7bb5c1874736c8cde7edf1773a22f89
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xE63B 19908 bytes
font_01_sfnt_off0001077e.bin
bcc24097af2b048876047dd4c25db8585abc60f4826ba87421f222944f0e4a5a
pdf-font-stream PDF embedded font (sfnt) at offset 0x1077E 11024 bytes
font_02_sfnt_off000120ff.bin
48faa3146a0bea4f86635b0b4edac3080d9b7800bcb60cd7f37dd07290dafa9c
pdf-font-stream PDF embedded font (sfnt) at offset 0x120FF 19876 bytes
font_03_sfnt_off00015024.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15024 16792 bytes