Malicious PDF — malware analysis report

Static analysis result for SHA-256 acf33a1c3daeb35c…

MALICIOUS

PDF

88.5 KB Created: 2021-07-09 18:13:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 29a1184ab3de7254d0239da183df8c09 SHA-1: 33d2859ddeadfb1fc80f28dcbf7e5463bd2ee2e6 SHA-256: acf33a1c3daeb35ceea2c04eaed8cc2e212481544741d60b9925bd1d134200ea
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, exhibiting characteristics of a malformed exploit stream. It contains a large number of external URIs, many pointing to compromised WordPress uploads, suggesting a link farm designed to redirect users. The PDF structure and embedded URLs indicate an attempt to deliver a malicious payload or phish for information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://smidgel.ru/uplcv?utm_term=list+the+5+components+of+physical+fitness PDF link annotation
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079ba6878737---lowetil.pdfIn PDF document text
    • http://bortran.com/upload/image/file/20210603092708.pdfIn PDF document text
    • http://angeladaniel.de/uploads/files/wuxifuvorened.pdfIn PDF document text
    • http://archerelectricsupply.com/userfiles/file/dudimulu.pdfIn PDF document text
    • http://au-zlato.sk/upload/files/68420313531.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086dfedbd50d---65702179374.pdfIn PDF document text
    • https://lee-trading.tw/archive/upload/files/xuduvolelobezapogonewem.pdfIn PDF document text
    • http://ya-ke.cn/admin/upload/16153599788.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/289cd80115c74107b6811277da8e6c55/zeziduzupinesirarodu.pdfIn PDF document text
    • http://htwy.com/upload/file/sazofuwerovi.pdfIn PDF document text
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/027885d8f84c99ae5afb25826d33d6ca/63175245136.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/81199380684.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad914310c40---lolululuvopomeguzavogir.pdfIn PDF document text
    • https://m-isc.com/userfiles/file/15187975696.pdfIn PDF document text
    • http://highlandlynxotic.com/clients/7/73/73cf6ae24f8ea70eb1cbac1dff6b0f9e/File/takap.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f75dc3ad82---42640560781.pdfIn PDF document text
    • http://agnieszkapawlik.com/userfiles/file/90408649165.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/8a2ae059595cbd77e79081d761b9159a/fatonajarebil.pdfIn PDF document text
    • http://lmyc.net/clients/875386/File/89279123812.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607a985e3c1f0---kudutiwabujefojemivod.pdfIn PDF document text
    • https://cafesca.mx/ckfinder/userfiles/files/90664993155.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608f564d11b9c---modadupa.pdfIn PDF document text
    • https://alutat.com/data/file/4258286287.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/digajoriwirupokuginuduvu.pdfIn PDF document text
    • https://www.autodepotperformancegroup.ca/wp-content/plugins/super-forms/uploads/php/files/8057ro4gbedoffdqinf0f1oige/11304738461.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/61a0da3a25f3916eae335d2a1030eb17/gomapavexudozenetoji.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://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_off0000f766.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF766 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010f7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F7D 10852 bytes
SHA-256: d98088a8ff565444bd746e63125bb849ba54e2b9dc325f01cf57db7e1c753449
font_02_sfnt_off00012871.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12871 16860 bytes
SHA-256: 86d0914d1125e3e7ccc6333b4b76cf3aa830c15b2bd63dbeec35a20f21dd426a