Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f56d5489f24a313…

MALICIOUS

PDF

82.1 KB Created: 2021-09-19 15:52:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4a4511aab8d6630f6e6136f9674b9175 SHA-1: 662b93e159ceafa842c89a71b26acea3876cc40e SHA-256: 5f56d5489f24a313a1ba5620f430c04e6a6bbb47b99f69e9d14a6950ed9d1aac
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics as malicious, including a ML classifier and ClamAV, indicating it is likely a phishing or malware distribution attempt. The document contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious content. No scripts were extracted, but the presence of multiple external URIs and the overall structure strongly suggest an attempt to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7642

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://synerhu.ru/uplcv?utm_term=arm+hex+converter PDF link annotation
    • http://nemdanangpho.com/uploads/2021-09-10/images/files/medeza.pdfIn PDF document text
    • https://kinhdoanhvaphapluat.com/img-dn/files/tituxa.pdfIn PDF document text
    • http://xn----7sbicwad4afgcgd5aph7d5e.xn--p1ai/ckfinder/userfiles/files/18294265850.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/8a8b4d8bf658ba6609d4ef4d4d1205e5/63923749210.pdfIn PDF document text
    • https://yellowstonewildlife.com/49194922726.pdfIn PDF document text
    • https://drakbera.com/ckeditor/ckfinder/userfiles/files/gijilajozukotexurusuruji.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/sezivozapul.pdfIn PDF document text
    • https://bursaphotofest.org/uploads/files/31759753152.pdfIn PDF document text
    • https://bizimpin.com/calisma2/files/uploads/jasejuvuzomi.pdfIn PDF document text
    • https://doitoutdoorz.com/file/LWbbpwat3OlznBhA.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/52348026122.pdfIn PDF document text
    • http://pbhdom.eu/userfiles/file/lonapolun.pdfIn PDF document text
    • http://tongkhomica.com/upload/files/kijotilixakatibisajolofi.pdfIn PDF document text
    • http://aroma-es.site/yamituki-n/uploads/files/33550694106.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/30613154676.pdfIn PDF document text
    • http://kommunikator.nu/demo/userfiles/file///97887179149.pdfIn PDF document text
    • http://acril.ru/ufiles/files/mofowuvani.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/cc5391f5a09735603268e0583a96254d/sasarezogirakorerorunigos.pdfIn PDF document text
    • https://astefin.ro/ckfinder/userfiles/files/33646860198.pdfIn PDF document text
    • http://khlongtoei-nfe.com/library/userfiles/file/6274240025.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/firinigarenizedupudef.pdfIn PDF document text
    • http://efuegypt.org/userfiles/file/saripelol.pdfIn PDF document text
    • http://monikaknoblochova.com/userfiles/file/vobakaziwev.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/2ccdeb982dc0ea8ce21fb31999a41de7/29082639954.pdfIn 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_off0000e58f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58F 10176 bytes
SHA-256: 01f0d631a9fea34d604fb678df15d0022b5815b960a0fc77267bca56a813ce83
font_01_sfnt_off0000fc2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC2E 18576 bytes
SHA-256: d700134bdcdebd4b249a60a3e73f7c6ace065e458d9f1da4212aae73eeb5360b
font_02_sfnt_off00012d49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D49 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1